Self-storage expansion: connect competing delivery dates to the funding trough

A self-storage expansion should have a dated absorption model, not just a stabilized occupancy target. The model must show new external customers, move-outs, internal transfers, achieved rent and when competing inventory becomes available. A facility opening across the trade area in month four can change the remaining lease-up path without changing the subject project’s construction budget.

Public Storage’s 2025 Form 10-K identifies competition and storage demand as factors that can delay rent-up or reduce cash yields on new space. Its disclosure supports testing those dependencies; it does not establish the subject market’s absorption rate. Public Storage, 2025 Form 10-K

Build a competing-supply calendar with confidence levels

For each nearby project, distinguish announced, approved, under construction and operating space. Record unit mix, location, expected opening, source date and confidence in the schedule. A permit may support a possible project without establishing that financing, construction or opening will occur. Refresh the calendar as evidence changes.

Connect each delivery scenario to a specific assumption: fewer net move-ins, additional concessions, lower achieved rent or longer marketing expense. Do not reduce all these variables automatically if they represent the same underlying demand loss. Explain the mechanism and retain a case where the competitor is delayed or does not open.

For the subject property, count internal transfers separately. Moving an existing customer into the expansion does not create a new customer for the combined facility. If the original unit remains vacant, the consolidated model must show the lost income there.

Hypothetical 100-unit expansion

Assume 100 equal-sized units open at the start of month one. All modeled customers are external net additions, after move-outs; no existing customers transfer. Achieved rent is $100 per occupied unit-month, with no concessions or bad debt. Incremental variable costs are $10 per occupied unit-month, fixed expansion costs are $2,500 monthly, and incremental debt service is $4,000 monthly.

The base case gains ten net occupied units per month until full. The competing-delivery case gains ten per month for three months, then five per month after a rival opens at the beginning of month four. Move-ins are assumed evenly distributed within each month, so revenue uses the average of opening and ending occupied units. Ending occupancy alone would overstate first-year revenue.

The base case generates $70,000 of first-year rent and reaches its largest deficit, $23,450, in month seven. The competition case generates $51,750 and reaches a $31,450 deficit in month eleven. A $25,000 lease-up reserve covers the modeled base trough with $1,550 remaining but is $6,450 short in the competition case.

These are incremental expansion cash flows only. Construction equity, closing costs, existing-property cash and any minimum operating balance are outside the table. If the existing facility is expected to subsidize the expansion, demonstrate that cash after its own debt and capital obligations rather than assuming it is available.

Separate physical occupancy from debt-supporting economics

At $100 rent and $10 variable cost, each occupied unit-month contributes $90 toward fixed costs and debt. Monthly break-even average occupancy is $6,500 ÷ $90, or approximately 72.22 units. The competition case reaches 75 units at month-end twelve but averages only 72.5 during that month, producing just $25 of positive monthly cash.

If achieved rent falls to $90 while variable cost stays $10, the break-even average rises to 81.25 units. The same physical absorption path would remain below monthly cash break-even at year end. This is why unit count, achieved rent and the timing convention need to remain visible together.

Define a decision gate for later phases

Before authorizing another phase, compare actual external net absorption, achieved rents, concessions and reserve use with the modeled paths. Identify the commitments that can still be deferred and those already binding. A phased design only provides flexibility when the remaining work and its financing can actually be paused under contracts and loan documents.

The lender package should include the supply calendar, monthly absorption ledger, cost assumptions, committed funding and maturity sensitivity. The investor can then decide whether to proceed, resize or delay based on a quantified funding requirement. A forecast reaching stabilized occupancy eventually is insufficient if the loan or available cash expires first.