If you’ve ever looked into selling your house for cash, you’ve probably wondered how the offer number gets calculated. You submit your address, someone walks through or asks a few questions, and a few days later you’re handed a number. But where does that number actually come from?

It’s a fair question and one that a surprising number of sellers never think to ask. Understanding the math behind a cash offer doesn’t just help you evaluate whether an offer is fair. It helps you understand the entire cash sale model: why offers come in below retail, what legitimately affects the number, and how to spot the difference between an investor who’s done their homework and one who’s guessing.

This article breaks it all down.

The Foundation: After-Repair Value

Every serious cash home buyer starts with the same number: After-Repair Value, or ARV.

ARV is what your home would sell for on the open market if it were fully renovated and in move-in condition. This isn’t a guess, it’s calculated using recent comparable sales (comps) in your immediate area. An investor looks at homes similar to yours in size, style, age, and location that have sold within the last three to six months, typically within a half-mile to one-mile radius depending on neighborhood density.

This is the same methodology a licensed appraiser uses. The difference is that a cash buyer isn’t appraising what your house is worth today, they’re projecting what it will be worth after they put money into it.

ARV is the ceiling. Everything else in the offer calculation works backward from that number.

The Repair Cost Estimate

Once ARV is established, the investor needs to estimate what it will cost to get the property to that after-repair condition. This is where experience matters enormously.

A seasoned investor has done enough deals to walk through a property and build a reliable scope of work. They’re looking at:

• Roof condition — age, material, visible damage, remaining life
• HVAC systems — age, efficiency, whether replacement is imminent
• Electrical and plumbing — panel capacity, visible deficiencies, code compliance
• Foundation and structural — cracks, settling, water intrusion
• Kitchen and bathrooms — the two rooms that drive the most value and the most cost
• Flooring, paint, windows — the cosmetic layer that buyers notice first
• Exterior and curb appeal — siding, landscaping, driveway, garage

The repair estimate isn’t just about what needs to be fixed. It includes carrying costs during the renovation, the months of mortgage, taxes, insurance, and utilities the investor pays while the work is being done plus the cost of the renovation itself. A full gut rehab on a Baltimore row house costs very differently than a cosmetic update on a well-maintained suburban split-level. Experienced investors know the difference because they’ve made both work and gotten both wrong.

The Investor’s Formula: The 70–75% Rule

With ARV and repair costs in hand, most cash buyers apply a standard investment formula to arrive at their offer. The most common version is known as the 70% rule:

Maximum Allowable Offer = (ARV × 70%) − Estimated Repair Costs

So on a house with an ARV of $250,000 and $40,000 in needed repairs:

• $250,000 × 70% = $175,000
• $175,000 − $40,000 = $135,000 maximum offer

The 30% that’s held back from ARV isn’t pure profit. It has to cover the investor’s financing costs (or opportunity cost of cash), holding costs during renovation, selling costs when they list the finished property (typically another 6–8% in commissions and closing costs), and their profit margin which is what makes the entire business model sustainable.

Some investors work at 75% in competitive markets or on properties that need lighter work. Others work tighter than 70% on high-risk properties with significant unknowns. The formula is a framework, not a fixed rule, but it’s the framework that drives most offers you’ll receive from serious buyers.

At Yes I Pay Cash, the current standard is the 75% rule across their Maryland, Pennsylvania, and New Jersey markets, which reflects the competitive Mid-Atlantic market conditions and their operational efficiency from over two decades of buying in this region.

What Moves the Number Up or Down

Within the formula, several factors can shift the offer in either direction.

Factors that strengthen an offer:

• Recent, strong comps in the immediate area
• Lighter repair scope (cosmetic vs. structural)
• Desirable location with consistent buyer demand
• Clear title with no liens or complications
• Flexible seller timeline (less urgency = more negotiating room for both sides)
• Properties where the ARV is very well-supported by multiple recent sales

Factors that reduce an offer:

• Deferred maintenance that’s harder to scope accurately (old knob-and-tube wiring, unknown foundation issues, aging mechanicals)
• Thin or soft comparable sales; fewer recent comps means more risk
• Environmental concerns (oil tanks, asbestos, mold)
• Title complications or outstanding liens that will need to be resolved at closing
• Difficult access for showing or inspection

One factor that doesn’t move the number as much as sellers expect: your emotional attachment to the property or what you paid for it. Cash buyers are calculating based on what the market will bear after renovation, not what the house means to you or what you originally invested. This isn’t callousness, it’s math. The investor is taking on real risk and real costs, and the offer reflects that.

 

 

National Franchises vs. Local Investors: Why It Matters

Not all cash buyers use the same process, and the difference matters to you as a seller.

National franchise buyers and iBuyers often generate offers algorithmically pulling data from public records and automated valuation models without ever seeing the inside of your house. The offer might seem reasonable on paper, but it frequently includes service fees (sometimes 5–7%), and the number is subject to revision after an inspection reveals conditions the algorithm couldn’t account for. Many sellers report receiving an initial offer, feeling good about it, and then watching it get adjusted downward after the company’s representative actually sees the property.

Local cash buyers like Yes I Pay Cash operate differently. They’re physically in the market. They know what a Baltimore County row house in Parkville actually sells for versus one in Hamilton. They’ve renovated properties on those same streets. When they give you a number, it’s grounded in firsthand market knowledge, not a zip-code-level algorithm.

This is also why a responsible local investor won’t give you a firm offer over the phone sight-unseen. The offer you receive after a walkthrough or photo assessment is the offer that holds. There’s no revision after you’ve already made plans.

It’s worth reading more about the full cost picture on both sides of this decision. A breakdown of what the traditional listing route actually costs sellers, including agent commissions, pre-listing repairs, carrying costs, and post-inspection concessions is covered in detail in this article on the hidden costs of selling a house the traditional way. The numbers may surprise you.

Is a Cash Offer Ever the Right Move Financially?

This is the honest question, and the answer isn’t always yes but it’s yes more often than sellers initially expect.

Consider what happens when you run the full comparison. A cash buyer might offer $185,000 on a house you believe is worth $230,000 on the open market. That gap looks like $45,000 on the surface. But when you layer in the actual costs of a traditional sale; agent commissions at 5–6%, pre-listing repairs, months of carrying costs, post-inspection concessions, and seller-side closing costs, that $230,000 listing price often nets somewhere between $175,000 and $195,000 in the best-case scenario.

Suddenly the gap between the cash offer and the net from a traditional sale is much smaller. And that’s before factoring in the time value of a fast closing, no open houses, no waiting, no financing contingencies that fall through two weeks before closing day.

For sellers who are time-constrained dealing with an inherited property, a foreclosure timeline, a job relocation, a divorce, or simply a house that needs significant work, the math frequently favors the cash route. For sellers with time, a move-in-ready property, and a strong local market, listing traditionally may still yield more. The key is running the actual numbers rather than comparing the list price to the cash offer in isolation.

How to Evaluate a Cash Offer You Receive

If you’re comparing offers or trying to assess whether an offer is reasonable, here’s a practical framework:

Step 1 — Establish your own ARV estimate. Look at recent sales of comparable homes in your immediate neighborhood. Zillow and Redfin show sold prices, not just list prices. Filter for similar square footage, bedroom count, and condition. This gives you a reality-check baseline.

Step 2 — Estimate your realistic repair costs honestly. Don’t mentally skip past needed repairs because you’ve lived with them. A cash buyer can’t. Get a rough contractor estimate if the property has significant deferred maintenance. This helps you understand why the offer came in where it did.

Step 3 — Model your actual net from a traditional sale. Take your estimated sale price and subtract agent commissions (5–6%), estimated repairs, three to five months of carrying costs, a buffer for post-inspection concessions (3–5%), and seller closing costs (1–3%). That’s your realistic net, not the list price.

Step 4 — Compare net to net, not gross to gross. The only fair comparison is what you actually walk away with in each scenario, not the offer price versus the listing price.

Step 5 — Factor in timeline and certainty. A cash closing in 7–14 days with no contingencies has real value. A traditional sale in 90–120 days with financing risk and inspection renegotiations carries real risk. Assign honest weight to both.

The Bottom Line

A cash offer isn’t a lowball by definition. It’s a calculated number based on ARV, repair costs, holding costs, and the investor’s required return and when you compare it to what you’d actually net from a traditional sale, the difference is often much smaller than the headline numbers suggest.

What separates a fair cash buyer in Towson, from one who’s just fishing for a distressed seller is transparency. A buyer who can walk you through their ARV estimate, explain their repair scope, and show you how they arrived at the number is a buyer who’s done the work. A buyer who throws a number at you over the phone without seeing the property is a buyer who will revise it later.

If you’re in Maryland, Pennsylvania, or New Jersey and want to understand what your specific property would look like through this lens, Yes I Pay Cash has been running this math on Mid-Atlantic properties since 2002 with over 600 transactions across Baltimore City and County, south central Pennsylvania, and New Jersey. Their Sell Your House Fast page explains the full process, and there’s no obligation attached to getting an offer.

The more you understand about how the number gets built, the better position you’re in, whether you end up selling for cash or taking the traditional route.

Keys to Your Property is a real estate resource hub covering home selling, investing, and property ownership topics across Maryland, Pennsylvania, and New Jersey.