How to Buy a Fourplex With a Conventional Loan and Low Down Payment

The Quick Read: To buy a fourplex with a conventional loan, you finance it as a primary residence by living in one of the four units. That can allow as little as 5% down on an automated approval. The key is occupancy. A fourplex you live in is underwritten as a principal residence, and one you don’t is treated as an investment property with a much lower leverage cap. The other three units can help you qualify, but only part of their rent counts, and you will usually need cash reserves on top of the down payment.

What Does “Fourplex” Mean to a Conventional Lender?

A fourplex is a two- to four-unit property, and lenders treat it as residential, not commercial. That is why a conventional loan can finance it at all. Five or more units move into commercial lending, which is a different world.

Across the wholesale programs Lendmire places files with, the dividing line is always the same: do you intend to live there? If yes, the loan follows owner-occupied rules. If no, it is an investment purchase, and the leverage drops to 75% on two to four units. That single choice moves the down payment from roughly 5% to 25%.

Lendmire’s conventional loan programs cover this owner-occupant lane. A fourplex you won’t live in belongs to a different kind of financing, and this article does not cover it.

How Is a Conventional Fourplex Loan Underwritten, Step by Step?

The process follows a fixed order. Each step feeds the next, and a weak spot at one stage tends to show up at another.

Step 1: Pick the occupancy

You must intend to live in one unit as your principal residence. With more than one borrower on the loan, only one has to occupy and take title, per Fannie Mae’s occupancy rules. Lenders check occupancy closely because the incentive to misstate it is built into the pricing difference. Treat it as a commitment, not a formality.

Step 2: Land on the right underwriting path

The 95% leverage on a fourplex is a result from automated underwriting, the system lenders run your file through. Per the Fannie Mae Eligibility Matrix, the manual path is much tighter: 85% on two units and 75% on three to four. Each figure is subject to lender guidelines and a complete review of property type, leverage, and credit.

Most wholesale conventional programs start at a 620 decision score, and the automated finding governs most files, with a total debt ratio ceiling of 50%. If your file only works manually, the fourplex math changes sharply. Subject to lender guidelines and full file review, a borderline file can lose its low-down option here.

Step 3: Qualify with the other units’ rent

This is where fourplex buyers get surprised. Rent from the unit you occupy cannot be used to qualify. Rent from the other three units can count, but not all of it. The standard calculation credits 75% of the gross monthly rent, with the remaining 25% covering vacancy and operating costs. Where there are no existing leases for those units, lenders use market rent from the appraisal.

On a principal-residence purchase, the full housing payment goes into your debt-to-income ratio. The rent is added to your income. It is not netted against the payment. So the rent helps, but it does not replace your own income.

Fannie Mae has also restricted subject-property rent for buyers with little rental or property-management history. The details have changed over time, so ask your loan officer how the current rule applies to you.

Step 4: Verify reserves

Fannie Mae’s reserve rules call for six months of reserves on a two- to four-unit principal residence. A one-unit home has no minimum. Automated underwriting can ask for more based on your overall risk. Reserves are cash you keep after closing, so plan for them separately from the down payment.

Step 5: Order the right appraisal

A fourplex is appraised on a multi-unit form, not the standard single-family report. The appraiser also produces a rent schedule with comparable rentals, and that schedule supports the rent figure the underwriter uses. This report takes more work than a one-unit appraisal. Appraisal waivers are generally not offered on two- to four-unit properties.

Step 6: Assemble the documents

Expect the usual income, asset and credit file, plus the purchase contract and any existing leases for each unit. Fannie Mae’s Quality Insider reports that miscalculated rental income or loss is a top issue in its random loan quality reviews, which is why lenders are strict about leases and worksheets.

How Much Down Do You Actually Need?

The floor on an owner-occupied fourplex is 5%, because leverage reaches 95% LTV. The 97% first-time-buyer option applies to one-unit homes, not fourplexes. On two- to four-unit loans above 80% LTV, some programs also require part of the down payment to come from your own funds, with the rest from other eligible sources. Leverage, reserves, and pricing vary by lender and program; the final terms follow the full file review.

Here is the tradeoff. A 5% down fourplex means a bigger loan, mortgage insurance and a thinner cushion if one unit sits empty. Putting 20% down removes the insurance and improves your margin for error. Either path can be right, depending on how much cash you want to keep in reserve.

Does Mortgage Insurance Apply?

Yes, above 80% LTV. Mortgage insurance protects the lender and is added to your monthly payment, as the CFPB explains. Published typical annual premiums run from 0.58% to 1.86% of the balance. That is a range, never a quote, and your actual cost depends on your credit and leverage. Terms vary by lender guidelines, property type, leverage, credit profile, and full file review.

It does not have to last forever. You can request cancellation at 80% of the original value with good payment history, no subordinate liens and no decline in value. The servicer must terminate it automatically at 78%. The Federal Reserve’s Homeowners Protection Act summary notes that these rules do not apply to high-risk loans. Ask whether a two- to four-unit property is covered before you count on the cancellation date.

Where the General Rule Breaks

The 95% headline holds in most cases, but several edge cases can change the answer.

• Manual underwriting. As in Step 2, leverage on three- to four-unit homes drops to 75%. Fannie Mae’s loan limits page shows that limits also scale with unit count and county, and the four-unit limit is far above the one-unit limit.
• Income-limited programs. HomeReady and Home Possible carry an income limit of 80% of area median income. HomeReady restricts borrowers to two financed properties, and its two- to four-unit option excludes condos and co-ops.
• Condos in a four-unit building. The appraisal form covers them, but the project gets its own eligibility review.
• Other financed properties. For a standard principal-residence loan, Fannie Mae sets no cap on how many properties you finance, and a multi-unit building counts as one.
• FHA as a comparison. FHA is not conventional, but buyers often compare it. HUD publishes separate four-unit limits in its annual announcement.

If you are not moving in, skip this article’s path. An investment fourplex is capped at 75%, and those loans work differently.

What Gets Fourplex Files Denied (and Fixes)

Most denials come down to three things: reserves, the debt ratio and rent documentation. All are visible before you make an offer, which is why a preapproval that models the fourplex specifically is worth more than a generic one.

What Does the Process Look Like in Practice?

1. Get preapproved, and tell the loan officer it’s a fourplex you’ll occupy.

2. Shop for properties with leases or a rent history you can document.

3. Write the offer, then order the multi-unit appraisal.

4. Submit leases, assets and reserve documentation.

5. Review your Loan Estimate and, later, the Closing Disclosure.

6. Move into your unit as planned.

Budget for a first-year operating picture too: taxes, insurance, vacancy, repairs and tenant management all fall on you. The 25% rent haircut in underwriting acknowledges those costs, so don’t treat the remaining 75% as profit.

A lower down payment makes the fourplex reachable sooner, but the strongest buyers are often the ones who hold back cash for reserves and a vacant unit. Wanting the 5% minimum is understandable. Needing it to make the deal work is a signal to look harder at price.

After Closing

Your occupancy commitment is real, so plan to live there. What happens after that depends on your circumstances and the lender’s terms, so confirm the specifics of your note. Once you reach 80% of the original value, mortgage insurance cancellation is something to ask your servicer about in writing. Some buyers repeat the strategy on a later primary residence, which is another reason to keep your reserves healthy.

If you are weighing leverage choices, Lendmire has a piece that walks through the mortgage-insurance tradeoffs in more depth, titled Can a First-Time Buyer Skip PMI on a Low Down Payment Conventional Loan?. For a related angle, there is Lendmire’s piece Is One Extra Payment Worth It on a Low-Down-Payment Conventional Loan?.

Key Terms Defined

LTV (loan-to-value): the loan amount divided by the lesser of price or appraised value.

Automated underwriting: the system that scores your file and determines the leverage you can use.

Reserves: liquid assets you hold after closing, counted in months of housing payments.

PMI (private mortgage insurance): coverage that protects the lender when you put down less than 20%.

Gross rent haircut: the 25% reduction applied to other units’ rent to account for vacancy and costs.

Super conforming: a loan above the baseline limit in a high-cost county, which can carry tighter leverage.

If you are buying a home and want to see whether a conventional loan fits your file, Lendmire can help you compare the options and what each one asks of the file. Lendmire is a mortgage broker, so it arranges these loans through wholesale lenders, and nothing here is a commitment to lend. You can reach the team at 828-256-2183.

For your own numbers, request a scenario review with Lendmire.

About Lendmire

Lendmire (NMLS# 2371349) is a mortgage broker licensed for consumer lending in 16 states. Lendmire arranges FHA, VA, conventional and jumbo purchase and refinance loans through wholesale lenders; every file is underwritten by the lender under the applicable program guidelines. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.

References

1. Fannie Mae’s occupancy rules

2. Fannie Mae Eligibility Matrix

3. Fannie Mae Selling Guide B3-4.1-01, Minimum Reserve Requirements

4. Fannie Mae Quality Insider

5. CFPB, Private Mortgage Insurance Guidance

6. Homeowners Protection Act summary

7. Fannie Mae’s loan limits page

8. HUD