A self-storage investor should reconcile occupancy and rental income by unit type, size, condition, and customer cohort. Unit occupancy, square-foot occupancy, economic occupancy, advertised rent, in-place rent, and collected revenue measure different things. Using them interchangeably can materially overstate performance.
The acquisition model should explain what customers actually pay, how concessions and turnover affect income, and which units remain difficult to rent. All examples below are hypothetical and do not state current Chicago storage rents, occupancy, or legal collection procedures.
Reconstruct the rentable inventory
Obtain a unit-by-unit schedule with dimensions, rentable area, type, location, climate features, access, condition, status, asking rate, in-place rate, concession, and customer balance. Reconcile the schedule to the physical property and management system.
Separate rentable units from offices, corridors, mechanical areas, unusable spaces, and proposed expansion. Gross building area is not net rentable storage area. An investor should understand which denominator each metric uses.
Investigate units marked unavailable, damaged, reserved, company-use, delinquent, or otherwise excluded. A reported occupancy figure can look stronger when difficult inventory is removed from the denominator without explanation.
For Chicago parcels, verify the lawful use and any proposed changes through the appropriate advisers. The city’s zoning framework provides the starting point, but a general commercial label does not establish permission for every storage configuration or expansion. Chicago zoning atlas provision
Calculate several occupancy measures
Unit occupancy divides occupied units by rentable units. Square-foot occupancy divides occupied rentable area by total rentable area. Economic occupancy requires a clearly defined revenue denominator and should be explained rather than assumed.
A facility can have high unit occupancy but lower area occupancy if large units are empty. Conversely, a few large occupied units can make area occupancy look strong while many small units remain vacant.
Use monthly averages and period-end measures distinctly. A year-end occupancy snapshot does not establish the occupancy that generated annual revenue. Seasonal move-ins and move-outs can affect both timing and customer acquisition cost.
Public Storage’s annual filing provides a primary example of how a large operator describes inventory and operating metrics. Read its definitions before making comparisons and do not present national portfolio results as local property benchmarks. Public Storage 2025 Form 10-K
Reconcile advertised, contractual, and achieved rent
An online move-in rate can differ from an existing customer’s rate. Promotions, free periods, discounts, fees, bad debt, and mid-period changes affect realized revenue. Build a bridge from the unit schedule to actual collections.
Ask how the operator changes rates and what customer behavior follows. Higher prices may increase revenue from retained customers while also causing move-outs or requiring new-customer concessions. Underwrite net results rather than a rate increase alone.
Review customer cohorts by tenure, unit type, and rate. A facility supported by long-term customers at higher in-place rates can have different transition risk from one recently filled through discounts.
Extra Space Storage’s filing provides another primary source for operating risks and metric definitions in the sector. Use both operator disclosures to develop questions, then verify the target property’s own records. Extra Space Storage 2025 Form 10-K
A hypothetical unit-mix analysis
Assume a facility has 100 small units of 50 square feet and 100 large units of 150 square feet. Total rentable area is 20,000 square feet. Ninety small units and 70 large units are occupied.
Unit occupancy is 160 ÷ 200 = 80%. Occupied area is 4,500 plus 10,500, or 15,000 square feet. Area occupancy is 75%. A single 80% occupancy headline conceals weaker utilization of the larger inventory.
Suppose occupied small units pay $80 monthly and large units pay $180. Scheduled occupied rent is $7,200 plus $12,600, or $19,800 monthly. Concessions and collection loss of $1,500 reduce it to $18,300 before other income.
Annualizing $18,300 produces $219,600 only if the month is representative and conditions persist. A full-year model should use monthly occupancy, rates, turnover, and concessions rather than treating a favorable snapshot as stabilized income.
Test whether the unit mix fits demand
Review inquiries, reservations, move-ins, move-outs, waitlists where credible, discounting, and vacancy by type. Ask which sizes are repeatedly unavailable and which remain empty despite marketing.
A physical conversion can change mix, but investigate construction, doors, circulation, systems, approvals, downtime, and net rentable area. Dividing a large unit does not necessarily create fully rentable small units at the assumed rate.
Compare incremental cash flow with complete conversion cost. Include the value of rent lost during work and the risk that observed demand is temporary. A small sample of inquiries should not become a precise long-term forecast.
Consider competing supply. Nearby facilities may offer similar sizes, access, climate control, technology, or promotions. The relevant market is defined by customer alternatives rather than a fixed municipal boundary.
Normalize operating expenses and ancillary income
Review staffing, management, marketing, software, payment fees, utilities, taxes, insurance, security, repairs, and administration. A seller using unpaid owner labor may understate the cost of operating the asset.
Separate recurring storage income from fees, merchandise, insurance-related income, or other services. Understand ownership, regulatory, contractual, and accounting treatment through qualified advisers. Do not capitalize gross ancillary collections without associated costs and obligations.
Investigate customer acquisition spending and online channel dependence. A lower management fee may be offset by higher marketing or technology costs. Compare total operating capability and expense.
Include capital needs for roofs, doors, paving, gates, security, climate equipment, and systems. A high operating margin does not establish low capital requirements.
Review collections and customer rights properly
Examine receivables aging, payment plans, write-offs, refunds, disputed charges, and the actual collection record. A unit marked occupied with a large delinquency may not produce supportable recurring income.
Counsel should review contracts and applicable procedures for notices, liens, access, disposition of property, and other customer rights. This guide does not prescribe those legal steps. The acquisition should not assume every delinquent balance is immediately collectible.
Determine how customer deposits, prepaid amounts, credits, and unresolved matters transfer at closing. They affect the owner’s obligations and opening cash position.
Audit a customer cohort through its first year
Select a group of customers moving in during the same month and follow scheduled charges, concessions, rate changes, payments, move-outs, refunds, and write-offs. Compare the cohort’s realized revenue with the marketing assumption used to attract it.
For a hypothetical group of 20 units advertised at $100 monthly, full twelve-month scheduled revenue would be $24,000 if every customer stayed and paid. A one-month promotion reduces that by $2,000. If five customers leave after six paid months rather than staying for the full paid period, actual collections fall further, depending on timing and replacement. New move-ins may require another promotion and customer acquisition cost.
The cohort view helps distinguish a high move-in rate from durable revenue. It also reveals whether existing-customer increases improve net results after additional move-outs. Avoid projecting all current customers through a full year at the latest in-place rate without turnover.
Reconcile operating-system revenue to bank and financial records. Payment processing, prepaid amounts, refunds, fees, taxes where applicable, and timing can create differences. An unexplained difference is a question to investigate, not an automatic adjustment in the buyer’s favor.
Use unit-type cohorts where the mix is material. Small climate-controlled units may have different tenure and pricing behavior from larger drive-up units. The investor should understand which categories drive margin and which consume marketing or capital without earning the forecast rent.
Link the findings to valuation and reserves. A facility recently filled through promotions may need a different stabilized income assumption from one with a mature customer base and supported collections. Neither is necessarily unattractive, but the transition should be visible.
For acquisition reporting, retain a short metric dictionary defining occupancy, available inventory, achieved rent, concessions, delinquency, and net collections. Require the seller or manager to explain changes in definitions across periods. A trend can reverse when a denominator or reporting convention changes, even if customer behavior does not.
The most useful revenue model can be reproduced from customer records and physical inventory. It shows not only how many units are occupied today, but how cash is generated and retained as customers enter, pay, change rates, and leave.
Review manual overrides in the operating system, including unavailable units, discretionary credits, and altered move-out dates. Those entries can affect reported occupancy or revenue and should have an explanation and supporting authorization.
Stress pricing and occupancy together
A competing facility can lower move-in rates while attracting customers away. Test lower achieved rent, more concessions, higher move-outs, and marketing cost in combination where plausible.
Model the resulting NOI and debt coverage, then include required capital and reserves. A facility can remain physically busy while cash generation weakens.
For exit valuation, use supportable stabilized revenue and actual operating costs. A buyer may discount aggressive rate assumptions or a customer base recently filled through temporary promotions.
Proceed when the unit inventory, customer economics, operating system, and capital plan support the investment. Reprice for weak mix or inflated revenue assumptions. Decline when returns depend on advertised rates that actual customers have not sustained.