The cheapest listing is frequently the most expensive deal. Here's the due diligence that separates a good rate from a good lease — with two calculators to run your own numbers.
Base rent is not what you pay.
Pass-throughs can add 30–100% on top.
Industrial and retail tenants get surprised by pass-throughs. Office tenants get surprised by load factor — paying rent on 15–25% more space than they can furnish. Either way the lowest asking rate is frequently the highest total cost. These seven checks catch it before signature, while you still have leverage.
TL;DR
Before leasing business space, verify seven things: location fit for your operating model, layout and clear height, total occupancy cost including CAM pass-throughs, building infrastructure capacity, zoning and permitted use, exit and renewal options, and landlord track record. The most common and most expensive mistake is comparing asking rents against each other. Triple-net pass-throughs alone can add 30% to 100% above the quoted face rate depending on property type and market — so a $24/SF quote and a $32/SF quote can easily land in the opposite order once you model the full term. The first three checks are pure desk research — location, zoning, and cost will eliminate most of a shortlist before you tour anything.
Jump to: The 7 Checks · Clear Height Calculator · Occupancy Cost Calculator · Rentable vs Usable SF · 2026 CAM Benchmarks · Tour Questions
Here are the seven, in the order they should be checked. The first three are desk research — you can eliminate properties with a laptop and a phone call before touring anything. Items 4 and 5 need a site visit and landlord documentation. The last two are negotiation-stage, and they're only available to you before signature.
| # | What to verify | Why it eliminates properties | Stage |
|---|---|---|---|
| 1 | Location and access | Wrong access profile can't be fixed by negotiation | Desk |
| 2 | Zoning and permitted use | A legal "no" ends the conversation | Desk |
| 3 | Total occupancy cost | Pass-throughs can double the face rate | Desk |
| 4 | Layout and physical fit | Clear height, floor plate, or venting limits are costly to change later | Site visit |
| 5 | Infrastructure capacity | Power and dock upgrades run months to years | Site visit |
| 6 | Exit, renewal, expansion rights | Only negotiable before signature | Negotiation |
| 7 | Landlord and management | Determines your next 5–10 years of operations | Negotiation |
Location means something different for every property type. Retail tenants are buying visibility and trade-area demographics. Warehouse and industrial tenants are buying highway access, labor pool proximity, and truck maneuverability. Office tenants are buying commute radius and talent draw. A location that scores well for one is often actively wrong for another.
Every property type: research planned construction, road projects, or rezoning within a mile. A road widening or a new interchange can move access and value in either direction, and a five-year lease outlasts most construction timelines.
A property where the only truck route runs through a residential corridor. Those restrictions get enforced, and they usually surface after you've signed.
A space can be physically perfect and legally unusable. Zoning verification confirms your specific business activity is permitted — not a similar-sounding one. This bites office and medical tenants as often as industrial ones: headcount is capped by egress capacity, and a change of use in an older building can trigger accessibility upgrades nobody budgeted for.
Variance applications take time and have uncertain outcomes. Treat a required variance as real risk, not a formality — and never sign a lease contingent on one without a clean out if it's denied.
This is where most leasing decisions go wrong. Total occupancy cost = base rent + pro-rata operating expense pass-throughs + escalations over the full term + one-time costs (buildout beyond the TI allowance, moving, signage, permits).
Your pro-rata share is your leased square footage divided by total leasable square footage. A 5,000 SF tenant in a 50,000 SF building holds a 10% share, so 10% of eligible expenses lands on their ledger.
Enter a quoted deal. See what you'd actually pay across the full term.
Enter rentable square feet — that's what rent is billed on. Full-service office tenants should enter $0 for CAM and model base-year increases separately. Excludes buildout beyond TI allowance, free rent concessions, moving, signage, and permits. A tenant rep broker models net effective rent across competing properties so you compare total cost, not face rent.
Comparing a $32/SF NNN quote against a $44/SF full-service quote without adjusting is not a comparison at all.
| Structure | Who pays taxes, insurance, CAM | Common for |
|---|---|---|
| Triple net (NNN) | Tenant, on top of base rent | Retail and industrial |
| Modified gross (MG) | Split — landlord covers a base year, tenant pays increases above it | Office |
| Full service gross (FSG) | Landlord, inside base rent (increases above base year may still pass through) | Office, especially urban |
A widely repeated error worth correcting: NNN is not the default across all commercial property. It dominates retail and industrial, while office space is frequently quoted modified gross or full service. In Manhattan, for instance, office rents are conventionally quoted on a full-service basis.
Office tenants have their own version of the triple-net surprise, and it hides in the area, not the expenses. You pay rent on rentable square feet (RSF), but you can only occupy usable square feet (USF). The gap is your share of lobbies, corridors, restrooms, and mechanical rooms.
Load factor = RSF ÷ USF, shown as a multiplier. A 1.20 load factor means you pay for 20% more space than you occupy. Typical office multipliers run 1.15 to 1.25.
Loss factor = (RSF − USF) ÷ RSF, shown as a percentage of the total. Loss factors generally run 15% to 30%, with Class A buildings carrying large lobbies and extensive amenities at the high end. Same relationship, opposite angle.
You need 8,000 usable square feet. The building carries a 1.20 load factor, so your lease is written for 9,600 RSF. At $38/SF:
Over a five-year term that's $304,000. The load factor isn't illegitimate — it's how shared space gets allocated — but the rate alone tells you nothing about whether it's accurate.
Don't confuse the two. The load factor determines the area your rent is calculated on. CAM and operating-expense pass-throughs are a separate charge allocated in proportion to your rentable space, governed by different lease provisions. A building can have a fair load factor and abusive CAM, or the reverse.
Know which standard applies, too. Most of the U.S. follows BOMA; New York City and the surrounding tristate area largely follow REBNY. BOMA measures from the centerline of the exterior window while REBNY measures from the exterior face, which adds square footage — one reason New York loss factors tend to run above the national average. The BOMA 2024 update also brought certain outdoor amenities into rentable area and changed how unenclosed spaces like balconies and terraces are treated, so an older lease and a new remeasurement can disagree.
In a full-service or modified-gross lease the landlord covers operating expenses up to a base-year amount, and you pay your share of increases above it. A base year set artificially low, or one set before a tax reassessment, hands you increases in year two. Confirm which calendar year it is and what's in it.
Building standard hours are often 8–6 weekdays with limited Saturday service. Anything outside that is typically billed hourly. Parking may be excluded from rent entirely and charged per stall per month. Both are real monthly costs that never appear in a $/SF quote.
If your quoted CAM falls well outside the range for your property type, that alone justifies asking for three years of reconciliation history.
| Property type | CAM per SF/yr (2026) |
|---|---|
| Light industrial / flex | $1.50 – $3.00 |
| Community / neighborhood retail | $3.00 – $6.00 |
| Strip mall / power center | $4.00 – $8.00 |
| Class B suburban office | $5.00 – $9.00 |
| Class A suburban office | $7.00 – $11.00 |
| Class A urban office (CBD) | $12.00 – $18.00 |
| Regional mall (in-line tenant) | $8.00 – $14.00 |
Across property types, NNN charges broadly run $3–$16/SF depending on building class, age, and market. For base rent context, see TenantBase's industrial, retail, and office cost guides.
Commonly negotiated at 5–7% annual increase, with taxes and insurance carved out as uncontrollable.
A roof replacement or lot repaving is capital, not maintenance. If your lease excludes or amortizes capital items, those charges are improper on a CAM statement.
The right to inspect the landlord's books, with a defined window and cost-shifting if the audit finds a material overcharge.
In multi-anchor retail, anchors often self-maintain their areas — their expenses leave the CAM pool, but landlords sometimes leave their square footage in the denominator. In-line tenants end up subsidizing a share nobody is paying. Also check for a gross-up clause, which adjusts variable expenses to full-occupancy levels in a partially leased building.
For industrial and warehouse space this is mostly about one number, so we start there — but office and retail tenants have their own hard constraints further down, and they're just as expensive to discover late. Clear height is the vertical distance from the finished floor to the lowest immovable obstruction — a sprinkler deflector, HVAC duct, light fixture, joist, or beam. It is not the roof peak, and it is not what the listing says. Older buildings frequently have inconsistent heights across bays, so measure at multiple points.
Work backward from your racking, not forward from the building.
Planning figure only. Actual allowable storage height depends on commodity classification, rack configuration, and sprinkler model. Confirm with a fire protection engineer during due diligence.
ESFR systems are often described as letting you stack higher. That's an oversimplification worth correcting, because it costs tenants money.
ESFR can reduce or eliminate the need for in-rack sprinklers in certain high-piled storage configurations. But it requires more deflector clearance, not less — generally 36 inches between the deflector and the top of storage, versus 18 inches for standard systems. OSHA independently requires the same 18-inch minimum under 29 CFR 1910.159(c)(10).
Clear height is irrelevant in a Class A tower. These are the equivalents — the physical limits that decide whether a floor plate works, and that cost real money to change after signature.
Industrial, also verify: column spacing, office-to-warehouse ratio, and floor load capacity in pounds per square foot against your heaviest equipment and rack post loads.
Power is now the constraint that surprises tenants most, across every property type. In several U.S. markets, securing additional electrical capacity from the utility can take years, not months — which means power availability should be confirmed before a building makes your shortlist, not during lease negotiation.
A landlord who offers a verbal assurance about power capacity but won't produce the utility documentation.
Every flexibility provision is negotiable before signing and effectively unavailable after. This is the section tenants regret skipping.
Expect landlords to price flexibility, usually as slightly higher base rent or a tighter notice window. That trade is often worth making. Most of these rights lapse if you miss a notice deadline, so calendar them the day you sign.
You'll work with this landlord and their management company for five to ten years. Their responsiveness affects operations daily; their financial condition affects whether TI commitments get honored.
This is the factor hardest to replicate independently. Brokers who have closed multiple deals in a submarket know which ownership groups honor commitments and which litigate.
| Factor | Retail | Warehouse | Industrial | Office |
|---|---|---|---|---|
| Street visibility / foot traffic | Critical | Minimal | Minimal | Low |
| Highway and freight access | Moderate | Critical | Critical | Low |
| Transit access (rail / bus) | Low | Low | Low | Critical |
| Talent pool / commute radius | Low | Moderate | Moderate | Critical |
| Clear height | Low | Critical | High | N/A |
| Dock door count | Low | Critical | High | N/A |
| Load factor / measurement | Moderate | Low | Low | Critical |
| Parking ratio | Critical | Moderate | Moderate | Critical |
| Electrical capacity | Moderate | High | Critical | Moderate |
| HVAC zoning & after-hours | Moderate | Low | Low | High |
| Telecom / fiber redundancy | Moderate | Moderate | Moderate | Critical |
| Signage rights | Critical | Low | Low | Moderate |
| Typical CAM ($/SF/yr) | $3–$8 | $1.50–$3 | $1.50–$3 | $5–$18 |
| Common lease structure | NNN | NNN | NNN | MG / FSG |
Why transit and talent pool rank Critical for office: for industrial and retail, location is mostly about moving goods or customers. For office, location is a recruiting and retention tool. A site a rideshare or a long walk from the nearest rail or bus line quietly shrinks your hiring pool and shows up later as turnover. Commute radius works the same way in reverse — map where your current staff actually live before you sign, not just distance on a map from downtown.
Tours are for verifying what listings can't convey. Arrive with documentation requests, not just questions.
Clear height at the lowest obstruction in multiple bays · electrical amperage and available capacity · sprinkler type and last inspection · floor load rating in PSF · truck court depth · dock leveler condition and age · environmental history and any Phase I.
Visibility from each approach direction · foot traffic during your actual operating hours · permitted signage · co-tenancy and exclusivity provisions · anchor lease expirations · whether the anchor participates in CAM.
Load factor and how rentable SF was measured · base year for operating expenses · after-hours HVAC cost and availability · parking ratio and cost · building access hours · existing tenant density.
Ask for these at every property: three years of CAM reconciliation history, the current certificate of occupancy, and the landlord's standard lease form — so you're reviewing their paper before you're emotionally committed to the space.
A tenant rep broker works exclusively for the tenant, in contrast to a listing agent, who is engaged by and owes duties to the landlord.
“When you call the number on a sign, you are speaking with the landlord's representative — not yours.”
In most U.S. commercial markets, the landlord pays both brokers' commissions at lease signing, including the tenant rep's fee. This is how commercial real estate has worked for decades — most tenants simply don't know it, which is why so many negotiate unrepresented against a professional. Local market customs vary, so confirm the arrangement with your advisor.
Specialization is what makes representation valuable. A broker who has closed deals in your specific submarket and property type knows what's actually negotiable right now, which landlords are motivated, what concession packages are on the table, and what comparable deals look like. A generalist working outside their specialty doesn't have that intelligence — and the quality of your lease terms is directly shaped by it.
Founded in 2014, TenantBase is a technology platform — not a brokerage — that connects businesses with vetted local tenant rep brokers. Share your requirements once. Instead of becoming a lead distributed to five brokers who know nothing about your situation, you're matched with one licensed specialist chosen for your property type and submarket, already briefed on what you need.
Tap any question to expand.
Verify seven things: location fit for your operating model, layout and clear height, total occupancy cost including pass-throughs, infrastructure capacity, zoning and permitted use, exit and renewal rights, and landlord track record. Request three years of CAM reconciliation history and the landlord's standard lease form before you're committed to a space.
Add base rent to your pro-rata share of operating expense pass-throughs, then model annual escalations across the full term and add one-time costs like buildout beyond the TI allowance. Your pro-rata share is your leased square footage divided by total leasable square footage. Pass-throughs can add 30–100% above the quoted face rate.
→ Use the Occupancy Cost Reality Check calculator to model a specific deal.
Light industrial and flex space typically runs $1.50–$3.00 per square foot per year. Community and neighborhood retail runs $3.00–$6.00. Class B suburban office runs $5.00–$9.00, Class A suburban office $7.00–$11.00, and Class A urban office $12.00–$18.00. If a quote falls well outside the range for your property type, request three years of reconciliation history.
| Light industrial / flex | $1.50 – $3.00 |
| Neighborhood retail | $3.00 – $6.00 |
| Class B suburban office | $5.00 – $9.00 |
| Class A suburban office | $7.00 – $11.00 |
| Class A urban office (CBD) | $12.00 – $18.00 |
Usable square feet (USF) is the area you occupy. Rentable square feet (RSF) is USF plus your share of lobbies, corridors, restrooms, and mechanical rooms — and rent is billed on RSF. The relationship is the load factor (RSF ÷ USF), typically 1.15 to 1.25 in office buildings, or the loss factor ((RSF − USF) ÷ RSF), typically 15% to 30%. A 1.20 load factor means you pay for 20% more space than you can furnish.
In a full-service or modified-gross lease, the landlord covers building operating expenses up to a base-year amount, and the tenant pays a pro-rata share of increases above it. A base year set artificially low, or set before a tax reassessment, shifts increases onto the tenant as early as year two. Confirm which calendar year applies and what expenses are included in it.
Clear height is measured from the finished floor to the lowest immovable obstruction — typically a sprinkler deflector, HVAC duct, light fixture, joist, or structural beam. It is not the roof peak. Measure at multiple points, since older buildings often have inconsistent heights across bays.
→ Use the Clear Height Calculator to work backward from your racking plan.
Partly, but not in the way it's usually described. ESFR systems can reduce or eliminate the need for in-rack sprinklers in certain high-piled storage configurations, but they require more deflector clearance — generally 36 inches from the top of storage, versus 18 inches for standard systems under NFPA 13. Confirm allowable storage height with a fire protection engineer during due diligence.
In a triple net (NNN) lease the tenant pays base rent plus a pro-rata share of taxes, insurance, and common area maintenance. In a modified gross lease the landlord covers a base year of operating expenses and the tenant pays increases above it. In a full service gross lease the landlord covers operating expenses inside base rent, though increases above a base year may still pass through. NNN dominates retail and industrial; office is frequently modified gross or full service.
In most U.S. commercial markets, no. The landlord pays both brokers' commissions at lease signing, including the tenant rep's fee. Market customs vary, so confirm the arrangement with your advisor. TenantBase matches tenants with licensed local specialists at no direct cost to the tenant.
A listing agent is engaged by the landlord and owes duties to the landlord. A tenant rep broker works exclusively for the tenant — sourcing both listed and off-market options, running comparable analysis, and negotiating on the tenant's behalf.
When you call the number on a sign, you're speaking to the landlord's representative.
You share your requirements once — location, size, budget, timing — and TenantBase matches you with one vetted local tenant rep broker who specializes in your property type and submarket. TenantBase is a technology platform, not a brokerage, operating across 50+ U.S. markets with a 4.9-star rating from 968+ verified Trustpilot reviews.
Get Matched With a Specialist →Sources
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Fire protection, zoning, and structural requirements vary by jurisdiction and building. Confirm clear height, sprinkler criteria, slab capacity, and permitted use with qualified engineers and your local authority having jurisdiction during due diligence. This post is for informational purposes only and does not constitute legal, engineering, financial, or real estate advice. Commercial real estate transactions vary by market and circumstance.
TenantBase, Inc. is a technology platform. While TenantBase may hold corporate real estate licenses, it is not providing real estate brokerage or advisory services and does not represent any listings. TenantBase works with third parties, including listing entities and a network of independent licensed real estate professionals. TenantBase does not guarantee the performance or outcome of any match or connection.