Free Tool

House Hack Calculator

Enter your income and we'll estimate what you can afford. Pick a property, add your expected rent, and we'll tell you if it pencils out — the way a lender would actually run it.

1

Your Finances

We'll use this to estimate what you can afford before you even pick a property.

$/mo

Before taxes, all borrowers combined

$/mo

Car, student loans, credit cards, etc.

Have you been pre-approved?

No worries — we'll estimate for you

Based on your income and debts, we'll calculate roughly what you could qualify for. Getting pre-approved with a lender will give you exact numbers.

Your Rough Pre-Approval

$428,467

Based on your income and debts, a lender would likely approve you for a home around this price with FHA financing.

Current DTI

7.1%

DTI Headroom

49.8% remaining

Max Housing Payment

$3,483/mo

Loan Type

FHA (3.5% down)

Assumes good credit, FHA at 6.25%, ~2.5% annual costs. Does not include rental income offset. This is an estimate — get pre-approved with a lender for exact numbers.

2

Property & Loan Details

Property Type
Loan Type
$
%

Min 3.5% for FHA

%

30-year fixed rate (FHA avg ~6.25%)

3

Rental Income

$/mo
Do you have current leases?
Rent discount factor (Duplex):75%
Usable rental income (for DTI):$1,500/mo

Want more accurate numbers?

We're estimating ~$4,200/yr taxes and ~$3,600/yr insurance. Adjust these if you know the actuals.

Results

Your Buying Power

$428,467

Estimated max price before rental offset

This could work!

The rental unit offsets 51% of your payment — the lender credits $1,500/mo, bringing your net housing cost to $1,423/mo.

At 27.5% DTI, you're well within the 56.9% limit.

Total PITI

$2,923

Monthly payment

Your DTI

27.5%

Max 56.9%

Net Out-of-Pocket

$923

After full rent collected

Lender Credit

$1,500

75% of rent

Payment Breakdown

Principal & Interest$2,116
Property Tax$350
Insurance$300
FHA MIP$158
Total PITI$2,923
Lender rental credit-$1,500
Net housing (for DTI)$1,423

Using estimated costs (~$4,200/yr tax, ~$3,600/yr insurance). Click "Fine-Tune" on the left to adjust.

Want us to run real numbers?

Send us a listing and we'll help you figure out if it works for house hacking.

Book a Call With Us

ADU vs. Duplex: What Florida Buyers Need to Know

The #1 Thing Most Buyers Miss

The difference between an ADU and a duplex isn't about separate meters, separate entrances, or even how the property looks. It comes down to one thing: how the property is zoned. Single-family residential (SFR) zoning means the second unit is an ADU. Multi-family zoning means it's a duplex. This single distinction changes how much rental income a lender will count toward your qualification.

How Lenders Calculate Rental Income

When you buy a duplex (multi-family zoned), lenders treat it as a true multi-unit property. FHA and conventional guidelines allow you to count 75% of the rental income from the other unit to help you qualify, with no cap on how much of your total income that represents. The 25% haircut accounts for vacancy and maintenance.

An ADU on a single-family lot is treated differently. The lender first applies a discount factor — 75% of rent if you have an existing lease (50% under FHA if no rental history). But then there's a second restriction: the resulting ADU income cannot exceed 30% of your total qualifying income. This two-step rule, established by FHA Mortgagee Letter 2023-17 and Fannie Mae SEL-2025-08, exists because the property is still classified as a one-unit home and the ADU income is considered supplemental, not core.

Duplex

$2,000/mo rent × 75% = $1,500/mo qualifying income (no cap)

ADU

$2,000/mo rent × 75% = $1,500 → capped at 30% of your income

You Need a Lease

For multi-family properties (duplex, triplex, quadplex), lenders require a current, signed lease on the rental units to count any income at all. No lease means the lender treats the rental income as $0. ADUs are slightly different — lenders can use an appraiser's estimated rent, but having a lease still gets you a better discount factor.

The FHA Self-Sufficiency Test (Triplex & Quadplex)

If you're financing a 3-unit or 4-unit property with FHA, the property itself must be able to pay for itself. Here's the test:

  1. Appraiser estimates fair market rent for all units (including yours)
  2. That total is multiplied by 75% (25% vacancy/maintenance factor)
  3. The result must be ≥ your total PITI payment

If it fails, the FHA loan is denied — no exceptions. Your options are to switch to conventional financing (no self-sufficiency test), increase the down payment to lower PITI, or find a property with higher rents.

This test does NOT apply to duplexes, and conventional loans never require it regardless of unit count.

Reserve Requirements

Multi-unit properties require you to have cash reserves in your account after closing. This is money the lender wants to see as a safety net.

FHA

1-2 units: No reserves

3-4 units: 3 months PITI

Conventional

1 unit: Varies

2-4 units: 6 months PITI

How to Check a Property's Zoning (Florida)

  1. 1County Property Appraiser website — Search the address on your county's property appraiser site. In Pinellas County, that's pcpao.gov. Look for the "Land Use" or "Zoning" field.
  2. 2City zoning map — Most Florida cities publish interactive zoning maps. St. Petersburg's is at the city's GIS portal. Look for RM (Residential Multi-Family) vs. RS (Residential Single-Family) designations.
  3. 3MLS listing details — The MLS often lists "Property Sub Type" or "Zoning." If it says "Single Family" with an ADU mention, it's likely SFR zoned. "Duplex" or "Multi-Family" indicates multi-family zoning.
  4. 4Ask your agent — A good buyer's agent will verify zoning before you write an offer. This is exactly what we do for our clients relocating to Tampa Bay.

Florida-Specific Considerations (2026)

  • Florida SB 48/HB 313 (effective July 1, 2026) will require all 67 Florida counties to allow ADUs by right in single-family zones. St. Petersburg and Pinellas County already permit ADUs. However, zoning classification for lending purposes still matters — even if your city allows ADUs, the lender uses the zoning code on record to determine rental income treatment.
  • No state income tax means your gross monthly income goes further in Florida. This helps your DTI ratio compared to states with income tax.
  • Flood insurance can significantly impact your monthly payment. Many Tampa Bay properties fall in flood zones. Factor this into your calculations above.
  • Homeowners insurance costs in Florida have risen significantly. Get quotes early — the number can make or break a house hack.
  • Homestead exemption reduces your property tax by up to $50,000 in assessed value if it's your primary residence, which it will be if you're house hacking.

FHA MIP: It's for Life

If you put less than 10% down on an FHA loan, the annual mortgage insurance premium (MIP) stays on the loan for the entire 30-year term. Unlike conventional PMI, which drops off once you hit 20% equity, FHA MIP never goes away. The only way to remove it is to refinance into a conventional loan once you have enough equity. At 0.55% of the loan amount, that can add $200–$300/mo on a typical Tampa Bay purchase. Factor this into your long-term plan.

2026 Loan Limits — Tampa Bay

Loan limits cap how much you can borrow under each program. Tampa Bay is a standard-cost area, so these are the national floor limits.

FHA

1-unit (ADU): $541,287

2-unit (Duplex): $693,050

3-unit (Triplex): $837,700

4-unit (Quadplex): $1,041,125

Conventional

1-unit (ADU): $832,750

2-unit (Duplex): $1,066,250

3-unit (Triplex): $1,288,800

4-unit (Quadplex): $1,601,750

These limits apply to the loan amount, not the purchase price. A higher down payment can bring your loan under the limit.

This Calculator is an Estimate

This tool gives you a quick sense of whether a property pencils out. It is not a loan pre-approval. Actual qualification depends on credit score, full income verification, asset reserves, and your lender's specific overlays. Interest rates change daily — the defaults shown here are approximate as of early 2026. We recommend talking to a lender early in the process to get real numbers.