Sources and method

Every limit the tools apply comes from a program document, and every figure on the site carries the date of the document it came from. Rules were last checked against their sources on October 24, 2026.

Program rules

Rule set	Document	Date
Fannie Mae MHC loan terms (80% LTV, 1.25x, 50 sites, park-owned homes)	MHC term sheet	© 2026; read from the Internet Archive copy of April 21, 2026, because the Fannie Mae site blocks automated readers
Fannie Mae MHC eligibility and site leases	Multifamily Guide Part III, Ch. 6	Guide effective September 28, 2026
Fannie Mae occupancy floor	Multifamily Guide Part II, Ch. 1, Sec. 107.01	Guide effective September 28, 2026
Fannie Mae tenant site lease protections	Guide glossary and Part V, Sec. 420	Guide effective September 28, 2026
Freddie Mac MHC loan terms	Optigo MHC term sheet	April 2026 (footer 4/26)
Freddie Mac MHC eligibility and protections	Seller/Servicer Guide Ch. 22	Guide Bulletin update April 22, 2025
HUD 223(f) for manufactured home communities	Mortgagee Letter 2024-11	June 4, 2024
FHA multifamily mortgage insurance premium	90 FR 45789	September 23, 2025; applies to applications from October 1, 2025
SBA ineligibility	SOP 50 10 8.1 and 13 CFR 120.110	SOP effective October 1, 2026; eCFR current to October 22, 2026
Business-purpose credit and Regulation Z	12 CFR 1026.3	eCFR current to October 22, 2026

Live data

Treasury yields

The loan sizer starts from the 5, 7 and 10-year yields on the U.S. Treasury’s Daily Par Yield Curve. The date of the yields in use is printed under the spread field. A script reloads them before each deploy of the site. Between deploys, the sizer also checks this site’s /api/live endpoint, which reads a feed that pulls the Treasury curve every business day. When the feed has a newer day than the page, the yields, their date and every program estimate move to it. If the feed is down, the page keeps the yields it was built with.

Rates API and embed

GET /api/live?ids=UST5,UST7,UST10,SOFR returns each series’ latest value and date, the readings a week and a month earlier, a freshness status and the publisher’s link, as JSON with CORS open. Add &history=60 for 60 days of daily points. To show the same rates on another site, paste this:

<iframe src="https://mobilehomepark.loan/embed/rates?ids=UST5,UST7,UST10,SOFR" width="100%" height="150" style="border:0" title="Rates from Pad Count" loading="lazy"></iframe>

Treasury yields are U.S. government data. SOFR is from the Federal Reserve Bank of New York; its content is subject to the Terms of Use at newyorkfed.org, and this site isn’t affiliated with the New York Fed. If you republish what you take from here, credit “Data: Pad Count (mobilehomepark.loan)” with a link. No warranty. For bulk or commercial use, email hello@mobilehomepark.loan.

New manufactured home prices

The U.S. Census Bureau’s Manufactured Housing Survey, sponsored by HUD, publishes average sales prices of new homes by month of shipment, about five months after the month. The home page shows the latest month with its date. The table is read again every week, so a new month shows up within about a week of Census posting it.

How the tools calculate

Net operating income is collected income (lot rent from occupied pads, home rent, utility bill-backs and other income, less bad debt) minus operating expenses, including management as a percentage of collected income and reserves per pad and per park-owned home. Value is NOI divided by a cap rate you enter.

A loan is the smaller of value times the program’s maximum loan-to-value, and NOI divided by the program’s minimum coverage times the loan constant. The loan constant is the annual payment per dollar borrowed at the rate (Treasury plus the spread you enter) over the program’s amortization. The sizer then applies each program’s gates (pads, occupancy, park-owned share, quality level, borrower type, sponsor experience, minimum loan) and lists the ones the park fails.

The defaults in every field describe a made-up 80-pad park. They aren’t market data, and the spread and cap rates are placeholders, not quotes.

Why there is no park directory

The only national public dataset of parks is the DHS Homeland Infrastructure Foundation-Level Data (HIFLD) “Mobile Home Parks” layer. Its data.gov record says it was last updated on October 24, 2022, and lists no download. The HIFLD Open program was decommissioned and its public service no longer answers. Copies survive only in third-party archives, mixed with RV parks and mostly missing unit counts. A directory built on it would be out of date on day one, so we built tools instead.

What we don’t publish

Cap rates, bank terms and CMBS terms. No government or agency source publishes them, and a number we can’t source would be a guess. The tools ask you for them instead.