Storage Underwriter for iPhone
Professional self-storage acquisition underwriting from your iPhone. Enter the facts of a facility and see where it is today, where it can be at stabilization, and what that is worth to you.
Storage Underwriter is awaiting App Store approval. This page will link straight to the App Store listing once it is live. Until then, every calculator on this site runs the app's engine for free.
Eight stages from address to answer.
Each stage collapses to a one-line summary once it's done, so the whole deal is readable on one screen.
- PropertyPrice, rentable square feet, acreage, year built and notes.
- Unit mixEvery unit size with counts, occupancy, in-place, street and market rent, and climate control.
- OperationsAncillary income, collection loss and expenses: a quick ratio, or a line-item P&L that reconciles to it, with a post-sale property tax.
- FinancingAcquisition costs, a primary loan by LTV or amount with interest-only months, and an optional seller or secondary note.
- StabilizationTarget occupancy, months to stabilize, growth, and stabilized expense adjustments.
- ExpansionOptional added space by square feet or unit mix, with cost, construction time and lease-up.
- Hold & exitHold period, exit cap rate and selling costs.
- DashboardCurrent vs. stabilized NOI, NOI bridge, projection, returns, sensitivity grid and a verdict against your targets.
Sophisticated output from minimal input.
The figures below come from the app's built-in sample deal and are calculated by the same engine as the free tools on this site. They are not a screenshot.
NOI bridge
Sample deal- Going-in cap
- 6.28%
- Stabilized NOI
- $513K
- Levered IRR
- 25.1%
- Equity multiple
- 2.84x
- Stabilized DSCR
- 1.51x
- Break-even occ.
- 70%
What the app adds to the free calculators
- Saved deals. Keep every facility you look at, duplicate one to test a different offer, and reopen it months later.
- An 8-page PDF investment memorandum. Cover, property and unit mix, current operations, stabilization, financing, returns, sensitivity and risks, and assumptions, reconciled exactly with the dashboard.
- A line-item P&L with an estimate that fills whatever you haven't entered yet, so you always know how much of the expense total is still a guess.
- Expansion modeling by unit mix, inside the deal's IRR and NOI bridge.
- Your own targets. Set IRR, cash-on-cash, DSCR and yield-on-cost targets once; every deal gets a verdict and a list of risk flags against them.
- Private and offline. No account, no server, no analytics. Deals are stored only on your iPhone and are never deleted because a subscription ends.
Pricing
Storage Underwriter Pro is a subscription with two billing periods that unlock identical features: $49.99 / year or $2.99 / week (US prices; the App Store shows your local price). There is no free trial and no free tier inside the app. The calculators on this site are the free version of the math. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the period, and are managed in your Apple Account settings. See the Terms of Use.
Requirements
iPhone with iOS 17 or later. Works fully offline once Pro is active.
Questions
Is Storage Underwriter available on the App Store?
Not yet. It is awaiting App Store approval; this page will link to the listing as soon as it is live.
Is there a free trial?
No. The free calculators on this website run the same engine. The app is for investors who want saved deals, the full P&L and the PDF memo.
Does Storage Underwriter work for development deals?
It is built for acquisitions of existing facilities, including an optional expansion. It does not model ground-up construction draws or construction loans.
Is Storage Underwriter related to storageunderwriter.com?
No. Storage Underwriter for iPhone is an independent iOS app and is not affiliated with the website at storageunderwriter.com.
Where is my data stored?
Only on your iPhone, in Apple's on-device storage and your own device backups. There is no account and the app makes no network requests of its own.