About

Self-Storage Investor Blueprint is a free set of underwriting calculators and guides for people buying self-storage facilities. It is published by the independent developer of Storage Underwriter, an iPhone app for self-storage acquisition underwriting.

How the calculators work

Every calculator runs on a TypeScript port of the calculation engine inside the iPhone app. To keep the two in agreement, the app's Swift engine is compiled on its own and run over a fixed set of 23 deals, from simple to deliberately awkward (all-cash, interest-only, seller financing, expansions, invalid inputs). The website's engine must reproduce every output, to within rounding noise, before a change can ship.

The calculations run in your browser. Nothing you type is sent to a server. Your latest inputs for each calculator are saved in your browser's local storage so they're still there next time; clearing site data removes them.

How the guides are written

Guides explain underwriting concepts with worked examples that use hypothetical numbers, recalculated with the same engine. Market figures such as cap-rate surveys, and rules such as SBA program terms, are cited to their original publishers with dates. Markets and programs change, so treat any third-party figure as a starting point and confirm it before relying on it.

This site does not provide investment, lending, tax, legal or appraisal advice, and it is not written or reviewed by licensed professionals in those fields. Use it to organize your own analysis, then confirm the details with your lender, CPA, attorney and appraiser.

Independence

The site has no advertising, affiliate links or sponsored content, and it doesn't collect leads for lenders or brokers. The only thing it promotes is the Storage Underwriter app. Storage Underwriter for iPhone is not affiliated with the unrelated website at storageunderwriter.com.

Contact

Corrections and questions are welcome: gpmediacontact@gmail.com or 253-338-5428. See also Contact & support.