How Much Can You Borrow With an Investment Property HELOC on a Four-Unit Rental Property?

The Quick Read: Usually, an investment-property line on a fully rented four-unit building tops out at 70% combined loan-to-value (all loans on the property as a share of its value), minus every lien already on the building, up to a $500,000 maximum, if you hold title personally or in a revocable trust and carry a 700 or better credit profile. Every figure is subject to lender guidelines and a full file review.

• On an investment line, a higher score above the 700 floor buys eligibility but no extra leverage.
• The lender counts the full line limit against the ceiling, not just the amount you plan to draw.
• The minimum line is $25,000 and the maximum is $500,000, so thin equity or a very large building can both change the result.
• Rent is not what sizes this line. Your credit, your debt-to-income ratio, and your equity do.
• A four-unit building gets no special formula. It is simply the largest residential building these lines accept.

The Formula: Value, Ceiling, Then Subtract

Your maximum line equals the property’s value times 70%, minus the balance of your first mortgage and any other liens. The $25,000 minimum and $500,000 maximum then trim the result. Many investors expect to borrow against all their equity, but the ceiling is built to leave a cushion.

Here is the math in percentages of value, so you can drop in your own numbers:

Two details catch people. First, the lender measures the whole line limit, not your first draw. A 30% line that you only half use still counts as 30% against the ceiling. Second, the dollar cap can bind before equity does, mainly on higher-value buildings with light debt. Four-unit buildings often carry bigger balances and values than single-family rentals, so that is a real possibility, though your own numbers decide it.

Experian says lenders typically cap investment-property lines at 80% loan-to-value. On Lendmire’s wholesale network, an investment line is held to 70% CLTV, and no tier sits above it.

Lendmire’s DSCR work and its HELOC work are different tracks. If you want the rent-based side of the picture, the complete DSCR loans guide covers it.

Key Terms Defined

HELOC: a home equity line of credit, a revolving line secured by a property you already own.

CLTV: combined loan-to-value, which adds every loan on the property, including the new line’s full limit, and divides by value.

Lien: a recorded claim against the property, such as your first mortgage.

Draw period: the stretch when you can borrow from the line. On an investment line here, it runs five years with interest-only payments.

DTI: debt-to-income ratio, your monthly debts as a share of your monthly income.

Automated valuation: a software estimate of value used in place of a full appraisal.

What Shrinks Your Line Below the Formula?

Five things can pull the result under the 70% math: the dollar cap, your debt-to-income ratio, the valuation, your credit, and how title is held.

Debt-to-income. The maximum is 50%. The lender reviews your file on the interest-only payment at the maximum draw, so a large line can fail on DTI even when equity is plentiful. Rent from the building is not part of the line’s sizing. The line is underwritten on you.

Valuation. Lines at or below $500,000 ordinarily use an automated valuation, and an investment line never exceeds that size. A higher CLTV may call for a second valuation. You can also request a full appraisal. For a two-to-four-unit building, the traditional appraisal uses the small residential income property form, which Fannie Mae’s Selling Guide lists for two- to four-unit properties. That reference is only about the form’s name, since these lines follow their own guidelines. A lower value than you expected shrinks the ceiling dollar for dollar.

Credit. Seven hundred is the floor, with no tier beneath it. Scores above it affect eligibility, not the size of the line.

Title. The individual borrower or a revocable living trust must hold title. LLCs, corporations, partnerships, and irrevocable or land trusts cannot. A rental already deeded to an LLC needs a vesting change, or you can look at a DSCR cash-out, which can allow LLC ownership subject to lender program eligibility.

Exposure. A borrower is limited to three lines in total, and owning more than 15 financed properties makes you ineligible.

Does a Four-Unit Building Change the Number?

Not the formula. A fully rented four-unit building is underwritten as an investment property, so the 700 minimum, the 70% CLTV ceiling, and the $500,000 cap all apply. What changes is the building’s size and what that does to the math.

Four-unit properties sit at the top of what these lines accept. They are eligible whether they are standalone, townhome-style, or in a condominium or planned development project, including non-warrantable condos. A five-unit building is not offered, because commercial and mixed-use properties fall outside the program.

Because rent is not sized into the line, a vacant unit does not change the formula the way it would on a rent-based loan. The lender is looking at the property’s value, your liens, and your personal profile. How Much Can You Borrow on an Investment Property HELOC With One Unit Vacant? walks through that case.

One more practical point. Lenders weigh both your creditworthiness and the property’s financials, Yahoo Finance notes, and a HELOC sits as a second mortgage behind your first. Expect to provide a mortgage statement, proof of insurance, and ownership documents.

Owner-Occupied Fourplex vs. Fully Rented

Living in one unit changes the answer. If you occupy one unit, the building can be treated as a primary residence, and the network’s primary-residence ceiling reaches 90% CLTV. That figure exists only at a 720 or better credit profile. A fully rented building stays an investment property at 70%.

Say you own a fourplex with a first mortgage at 50% of value. As a fully rented building, your room under the ceiling is 20% of value. If you live in one unit and have a 720 profile, the ceiling moves to 90%, and the room grows to 40% of value, subject to the primary-residence rules and the dollar limits on that line. Occupancy has to be real and documented, so do not plan a loan around living there on paper.

Primary-residence lines can also exceed $500,000, up to $750,000, with a full appraisal and 700-or-better credit (720 on the longer-runway structure, which is one of two wholesale programs the lines run under). That only applies to the occupied building, not to a fully rented one.

How the Line Works After You Close

A HELOC is an open-end line you can draw on repeatedly during a draw period, followed by a repayment period. On an investment line here, that means five years of interest-only draw and 25 years of repayment. At least 75% of the line is drawn at closing, and the full line limit still counts against the ceiling. The payment can change over the life of the line, which matters more on a long-hold rental than on a quick flip.

You may have seen 75% quoted as the standard ceiling. That figure describes how limits are illustrated for owner-occupied homes in the broader market. It is an example of the method, not a rule for investment properties, where the ceiling on this network is 70% CLTV.

Seasoned investors often ask about the foreclosure risk. A default on a line secured by your rental puts that building at risk, and the added debt load can strain a portfolio. Tax treatment varies; consult a qualified professional.

HELOC or DSCR Cash-Out? A Quick Comparison

A HELOC leaves your first mortgage in place. A DSCR cash-out replaces it. That difference drives the choice.

DSCR compares rent to the full monthly payment, including taxes and insurance. Clearing 1.00 does not mean positive cash flow, because repairs, vacancy, management, and capital expenses sit outside the calculation. On a cash-out, about six months of seasoning is the common expectation. A cash-out on a four-unit building suits an investor whose first mortgage is small, or who wants to move title into an LLC. A HELOC suits an investor with a first mortgage worth keeping and personal income that supports the line.

Before You Apply: A Short Checklist

• Estimate your value, then multiply by 70%.
• Subtract your first mortgage and every other lien.
• Check that the result is at least $25,000 and no more than $500,000.
• Confirm your credit profile is 700 or above and your DTI fits under 50% with the full line at the interest-only payment.
• Confirm title is in your name or a revocable trust.
• Confirm the property is not listed for sale or recently listed, which can disqualify it in some states.
• Confirm you are in one of the 16 states where Lendmire offers these lines, which is narrower than its 41-market DSCR footprint.

Your Next Step

If you are considering a home equity line and want to see how the numbers work, Lendmire can help you compare HELOC options based on the property, the equity available, credit profile, combined leverage, and your goals. You can request a quote or call 828-256-2183. Lendmire is a mortgage broker that arranges financing through select lenders in its wholesale network. This is not a commitment to lend.

About Lendmire

Lendmire (NMLS# 2371349) is a mortgage broker. Home equity lines of credit — on a primary residence, a second home or an investment property — are arranged through wholesale lenders in Lendmire’s 16 full-service states, and every line is underwritten by the lender under its program guidelines. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.

References

1. Experian

2. Fannie Mae’s Selling Guide

3. Yahoo Finance — HELOC on an investment property

4. HELOC