The numbers

How to calculate your spread on a subject-to deal

Calculating your spread on a subject-to deal involves understanding the existing loan, your acquisition costs, and the property's potential value. It is more complex than a standard wholesale or flip calculation due to ongoing payments.

October 16, 2026 · 3 min read

What 'spread' means in a subject-to deal context

In a subject-to (sub-to) deal, 'spread' refers to your total potential profit. This is the difference between the property's market value (After Repair Value, or ARV) and your total costs, including the remaining mortgage balance, any arrears paid, repairs, and selling expenses.

Unlike a quick wholesale where you assign a contract for a fee, a sub-to deal means you are taking over the existing mortgage. Your spread is realized over time as you either sell the property or hold it as a rental, which impacts how you calculate it.

Identifying key financial components

Start by gathering all current financial details of the existing mortgage: the principal balance, interest rate, monthly payment, and if there are any arrears or missed payments. You will be responsible for these from the closing date.

Next, account for your acquisition costs. This includes any down payment you give the seller, closing costs, legal fees, and any necessary repairs to bring the property up to market standard. Every dollar spent reduces your potential spread.

Estimating the After Repair Value (ARV)

Accurately determining the ARV is crucial for any deal, especially a sub-to. This is the estimated value of the property once all necessary repairs and upgrades are completed. Pull recent comparable sales in the area that are in excellent, move-in ready condition.

Compare the subject property to these comps, making adjustments for differences in square footage, bedrooms, bathrooms, lot size, and features. Be realistic with your ARV; overestimating it can significantly shrink your perceived spread.

Calculating your equity position and profit margin

Your initial equity position is the ARV minus the current mortgage balance (and any junior liens). This is your potential gross profit before accounting for repair and selling costs.

To find your true spread, subtract all your estimated repair costs, holding costs (mortgage payments, taxes, insurance, utilities during your ownership), and eventual selling costs (commissions, closing costs) from that initial equity. This provides a clear picture of your net profit. Suppose your ARV is $250,000, and the existing mortgage is $150,000. That is $100,000 potential equity. If repairs are $30,000, holding costs $5,000, and selling costs $15,000, your net spread is $100,000 - $30,000 - $5,000 - $15,000 = $50,000. This is a hypothetical example.

Considering holding costs and selling expenses

Holding costs are often overlooked but can quickly eat into your spread. These include ongoing mortgage payments, property taxes, homeowner's insurance, and utility expenses for the period you own the property.

If your exit strategy is to sell, factor in real estate agent commissions, additional closing costs for the final sale, and any marketing expenses. A thorough accounting of these expenses will provide the most accurate spread calculation.

Questions people ask

Is the spread always higher on a subject-to deal?

Not necessarily. While a sub-to deal can allow for creative financing and potentially capture more equity than a straight wholesale, the spread depends heavily on the existing loan terms, the property's condition, and your exit strategy.

What if the existing loan has a high-interest rate?

A high-interest rate on the existing loan will increase your holding costs, which directly reduces your spread. You need to factor this into your calculations and consider if the property's ARV still justifies the acquisition under those terms.

How do I account for the principal paydown in my spread calculation?

When you take over the loan, the principal portion of each payment increases your equity over time. If you plan to hold the property long-term as a rental, this principal paydown is part of your return, but it does not factor into the immediate cash spread upon resale.