Skip to content
DealMath HQ

Owner-occupied investing

House Hack Calculator

House hacking means living in one unit and renting the rest. The number that matters is what your own housing ends up costing: PITI plus operating costs, minus the rent you collect. On the example below that is $1,318 a month against $1,900 of rent — $582 saved every month, on $27,300 of cash to close.

While you live there

Monthly, while you live there
Monthly, while you live thereAmount
Principal and interest$2,628.77
Mortgage insurance$185.76
Property tax and insurance$683.33
PITI$3,497.86
Maintenance and CapEx reserves, utilities$575
Rent collected($2,755)
Your net housing cost$1,318
After you move out
After you move outAmount
All 3 units rented, after vacancy$4,133
PITI($3,497.86)
Operating costs($575)
Monthly cash flow+$60
Cash-on-cash2.6%
Year-one principal paydown$4,319
The building

FHA and conventional owner-occupant loans cap at four

The alternative you are comparing against

Financing

FHA allows 3.5% on an owner-occupied 1–4 unit

FHA annual MIP is 0.55% on most 30-year loans

Operating

Of the whole building's scheduled rent

Why the financing is the whole strategy

A house hack is not a better building than an investment property. It is the same building bought on dramatically better terms, because you are going to live in it.

TermsDown paymentCash to closeLoan
FHA owner-occupant, 3.5%$14,700$27,300$405,300
Conventional owner-occupant, 5%$21,000$33,600$399,000
Investment property, 20%$84,000$96,600$336,000
Investment property, 25%$105,000$117,600$315,000

The gap between $27,300 and $117,600 is roughly four years of saving for most people. That, and not the cash flow, is what house hacking actually buys — it converts a multi-year savings problem into a one-year occupancy commitment.

What the mortgage insurance costs, and when it stops

FHA loans carry an annual mortgage insurance premium — 0.55% of the balance on most 30-year loans with less than 5% down — plus a 1.75% up-front premium usually financed into the loan. On a $405,300 balance the annual premium is $2,229, or $186 a month.

On FHA loans originated with less than 10% down, that premium runs for the life of the loan; it does not fall off at 20% equity the way conventional private mortgage insurance does. Escaping it requires refinancing into a conventional loan, which is why many house hackers plan a refinance at the point they have 20% equity.

The honest return calculation

Counting saved rent is legitimate — money not spent is as real as money earned. On this example, $6,986 of rent saved plus $4,319 of principal paid down over year one is $11,305 on $27,300 invested, a 41.4% first-year return. That figure is large because the capital base is tiny, not because the building is remarkable.

Common questions about house hacking

How do you calculate a house hack?
Take the full PITI plus operating costs for the whole building, then subtract the rent you collect from the units you do not live in. On the example here, $3,498 of PITI plus $575 of operating costs less $2,755 of collected rent is an effective housing cost of $1,318 a month — $582 less than the $1,900 the owner was paying in rent.
Why is house hacking cheaper than buying a rental?
Financing. An owner-occupant can buy a two-to-four unit property with an FHA loan at 3.5% down; the same building as a pure investment needs 20% to 25%. On a $420,000 triplex that is $14,700 versus $84,000 to $105,000 of down payment, and the owner-occupant rate is typically lower too.
Do I have to live there, and for how long?
Yes. FHA and conventional owner-occupant loans require you to occupy the property as your principal residence, generally within 60 days of closing and for at least twelve months. Lenders do verify, and occupancy misrepresentation on a federally-backed loan is mortgage fraud rather than a technicality.
Does rental income help me qualify for the loan?
Usually, partially. Lenders commonly credit 75% of documented market rent from the other units toward your qualifying income, using an appraiser's rent schedule. The 25% haircut covers vacancy and maintenance. Some programmes require landlord experience or reserves before they will count it at all.
What happens to the numbers when I move out?
Rent every unit and the building becomes an ordinary rental. On the example above that is $59 a month of cash flow — thin, because owner-occupant leverage of 96.5% leaves almost no equity cushion. House hacking is a strategy for cheap housing and a cheap entry, not usually for a strong stand-alone rental.

Once you move out, underwrite the building properly on the rental property calculator and check the loan on the DSCR calculator. If you are considering renting a spare room short-term instead, the short term rental calculator covers that maths.

The rest of the deal, on the same numbers

Your inputs are shared across every calculator on this site, so changing a figure here changes it everywhere.