House Hacking Calculator
Enter your property details, unit count, and expected rental income to see your net housing cost after tenant rent offsets your mortgage. Compare this against renting an equivalent home to see how much house hacking could save you each month.
Results are estimates for informational purposes only. Not financial advice. Full disclaimer.
What is House Hacking?
House hacking is a real estate strategy where you purchase a multi-unit property, live in one unit, and rent out the others. The rental income from tenant-occupied units offsets your mortgage and expenses, potentially reducing your housing cost to near zero — or even generating positive cash flow while you live there. The strategy is particularly powerful because owner-occupied properties typically qualify for more favorable financing. FHA loans, for example, allow as little as 3.5% down on properties with 2-4 units, as long as you live in one unit. This is significantly less than the 20-30% down payment generally required for traditional investment properties. Conventional owner-occupied loans typically require 5-15% down for multi-unit properties, still well below investment property requirements. House hacking works across a range of property types. The most common approach involves duplexes, triplexes, or fourplexes where you live in one unit and rent the rest. Some investors apply the concept to single-family homes by renting spare bedrooms or converting basements into rental units (where local zoning allows). The key principle is the same: use rental income to subsidize your own housing costs while building equity. Beyond the immediate cash flow benefit, house hacking accelerates wealth building. You are simultaneously reducing your housing expense, building equity through mortgage paydown, benefiting from property appreciation, and learning property management firsthand with the safety net of living on-site. Many successful real estate investors started with a house hack as their first property and used the experience and equity to scale into additional investments.
How to Calculate
- Enter the purchase price of the multi-unit property
- Enter your down payment percentage (FHA allows 3.5% for 2-4 units if owner-occupied)
- Enter the mortgage interest rate and loan term
- Enter the total number of units and how many you will occupy
- Enter the expected rent per unit for the tenant-occupied units
- Enter your estimated monthly expenses (property tax, insurance, maintenance, etc.)
- Review your net housing cost and compare against renting an equivalent unit
Formula
Monthly Mortgage = standard amortization formula using loan amount, rate, and term Loan Amount = Property Price × (1 − Down Payment Percentage ÷ 100) Total Rental Income = (Total Units − Owner-Occupied Units) × Rent per Unit Net Housing Cost = Monthly Mortgage + Monthly Expenses − Total Rental Income Equivalent Rent Cost = Rent per Unit × Owner-Occupied Units Monthly Savings = Equivalent Rent Cost − Net Housing Cost A negative net housing cost means the property generates positive cash flow even while you live there.
Example Calculation
For a $400,000 triplex with 10% down at 7%, 30-year term, renting 2 units at $1,200/month with $500/month expenses: Loan Amount = $400,000 × 0.90 = $360,000 Monthly Mortgage = $2,395.09 Total Rental Income = 2 × $1,200 = $2,400 Net Housing Cost = $2,395.09 + $500 − $2,400 = $495.09 Equivalent Rent = $1,200 (cost to rent a similar unit) Monthly Savings = $1,200 − $495.09 = $704.91 By house hacking this triplex, your effective housing cost is approximately $495/month — saving you roughly $705/month compared to renting an equivalent unit, while building equity in a $400,000 property.
Frequently Asked Questions
Can I use an FHA loan for house hacking?
Yes. FHA loans are one of the most popular financing options for house hacking because they allow as little as 3.5% down on properties with up to 4 units, provided you occupy one unit as your primary residence. You typically must move in within 60 days of closing and live there for at least one year. FHA loan limits vary by county and increase for multi-unit properties.
What are the risks of house hacking?
Key risks include vacancy (if a unit sits empty, you bear the full mortgage), maintenance costs that exceed projections, tenant issues (which are amplified when you live next door), and property value declines. There is also the lifestyle factor — being a landlord in your own home means less privacy and more responsibility. Budgeting conservatively for vacancy and maintenance generally helps mitigate the financial risks.
How many units can I house hack with owner-occupied financing?
Most owner-occupied loan programs (FHA, conventional, VA) allow up to 4 units. Properties with 5 or more units are typically classified as commercial and require commercial financing with higher down payments and different underwriting criteria. For most house hackers, a duplex, triplex, or fourplex is the sweet spot that balances income potential with residential financing advantages.
Do I need to report rental income from house hacking on my taxes?
Yes, rental income from tenant-occupied units is generally taxable and should be reported on Schedule E of your tax return. However, you can typically deduct the rental portion of expenses including mortgage interest, property taxes, insurance, maintenance, and depreciation. The owner-occupied portion is not deductible as a rental expense. Consulting a tax professional familiar with rental property is generally recommended to ensure proper allocation.
What happens when I move out of a house hack?
Once you move out, the property becomes a full investment property. All units generate rental income, which typically improves your cash flow. However, if you refinance later, you may face investment property rates and terms rather than owner-occupied rates. Some investors use a strategy of buying a new house hack every 1-2 years, converting each previous property into a full rental, and building a portfolio over time.