Shopping for a House? Here are 7 Key Home-Buying Numbers to Know

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There’s a lot that goes into buying a new home, starting with finding the right one all the way down to finalizing the paperwork. Somewhere in that process, you’ll likely find yourself trying to decipher myriad new terms and figuring out what they mean for you.

We’ve compiled this list of seven key numbers you’ll need to know when buying a home — plus the details on how understanding these terms can help you land your dream home.

Here are seven all-important home-buying numbers to know.

1. Cost per Square Foot

One of the first numbers you’ll encounter when shopping for homes is cost per square foot. While this number is based on a relatively simple calculation, it’s an important one to understand since ultimately it helps you determine how much house you’re getting for your money.

“Cost per square foot is simply the list price divided by the number of livable square feet,” said Tyler Forte, founder & CEO of Felix Homes. “This number is important because it allows a homeowner to compare the relative price of homes that are different sizes.”

But there’s more to consider, he said. “While cost per square foot is an important metric, you should also consider the layout of the home. In many cases, a home with an open floor-plan may seem larger even if it has a smaller livable square footage.”

Forte defines livable square footage as any interior space that’s heated and cooled, which is why a garage wouldn’t necessarily fit the bill. One of the best ways to understand how much home you can afford is to break it down by cost per square foot, which will vary from city to city and neighborhood to neighborhood.

Work with your real estate agent to understand the differences in cost for various properties to map out what areas and homes are within budget.

2. Earnest Money Deposit

Once you’ve found a home you like enough to bid on, you’ll quickly start hearing about something called an earnest money deposit (EMD). This is a type of security deposit made from the buyer to the seller as a gesture of good faith.

The amount of the EMD is set by the seller, typically running anywhere from 1% to 2% of the home’s purchase price. The key thing to keep in mind about EMDs is that they represent your commitment to buying the home, and can be useful in making a compelling offer in a competitive sellers’ market.

“An earnest money deposit is very important because it’s the skin in the game from the home buyer,” said Realtor Jason Gelios of Community Choice Realty. “If a home buyer is up against other offers, the EMD can make or break them getting the home.”

“I’ve seen lower offers won due to a higher EMD amount, because sellers view the higher EMD as a more serious buyer,” he added.

The money you put toward your EMD comes off the purchase price for the home, so there’s no reason to be stingy. If you really love the house and have the available cash, you might even consider offering more than the deposit amount your seller is asking. Either way, be sure to start saving up for your EMD early and factor it into any other cash you set aside for your down payment.

3. Interest Rates

Since most home purchases involve a mortgage, you’ll want to familiarize yourself with current interest rates. Interest rates dictate how much you’ll pay your lender every year to borrow the amount of your mortgage, so you’ll want to shop around for the best deal.

“Your interest rate is the annual percentage rate you will be charged by the lender, and the lower the rate you receive, the lower your monthly payment,” said real estate developer Bill Samuel of Blue Ladder Development. “You should speak with a handful of lenders when starting the process and get a rate quote from each one.”

While interest rates are mostly determined by your creditworthiness (aka credit score) and the type of loan you’re getting, they’ll still vary between lenders. Even a half-point difference in rates can amount to a big difference in your monthly mortgage payment — as well as the grand total you pay for your house.

4. Credit Score

Speaking of credit scores, you’ll want to know yours before you get serious about buying a home. Since your credit score helps determine the type of mortgage (and mortgage rate) you qualify for, you need to meet the basic minimum credit score requirements before diving headlong into buying a home.

Forte broke down the term a little more: “A credit score is the numerical grade a rating agency assigns to you,” he says. “Commonly referred to as a FICO score, this grade is made up of many factors such as credit utilization, and the length of your credit history.”

If your credit score is low (under 600), spend some time figuring out why and how you can boost it. Just remember, the better your credit score, the better your interest rate — and the more money you’ll save in the long run.

5. Debt-to-Income Ratio

Another personal finance term that comes into play when buying a home is your debt-to-income ratio (DTI). Much like creditworthiness, this number is used by lenders to determine how much of a loan you qualify for and at what rate.

“When looking to get approved for a mortgage, a buyer should know what their debt-to-income ratio is,” said Gelios. “This is the amount of debt you owe per month as compared to your gross monthly income.”

For example, if you earn $6,000 per month but have to pay $3,000 in bills, this would be a debt-to-income ratio of 50%. Gelios says lenders typically view any DTI above 40% as high risk, and with good reason. If over half of your income is accounted for in bills, that would make it significantly harder to make a big mortgage payment every month.

Understanding your DTI isn’t just good for lenders, it also helps put your personal finances in perspective when deciding how much house you can afford.

6. Down Payment

The all-important down payment: Many homebuyers use this number to help them determine when they’re actually “ready” to buy a home — based on how much of a down payment they have saved up.

“A down payment is the amount you contribute to the transaction in cash,” said Forte. “Most home purchases are a combination of cash in the form of a down payment and a loan from a mortgage company.”

The old rule of thumb on home purchases was to put down 20%. If that sounds like a lot of money, it is. (Home price $250,000, time 20% = $50,000. Ouch.) For many buyers, a 20% down payment just isn’t feasible — and that’s okay. Forte said the down payment can be as low as 3% of the sales price with a conventional loan, although 10% is more typical.

Remember that any amount you pay up front will ultimately save you money in interest on your mortgage — and putting more money down will lower your monthly payment. Take some time to calculate what your monthly mortgage payment will be based on various down payments. That way you’ll know exactly what to expect and how much of a down payment you should aim to save up.

Pro Tip

Keep in mind that for any down payment of less than 20%, you may be required to pay private mortgage insurance (PMI), another expense that adds to your monthly payment. 

7. Property Taxes & Other Expenses

Long before you close on a home, you need to be ready for ongoing expenses such as property taxes, homeowner’s insurance and any potential HOA fees. These expenses tend to slip through the cracks, but it’s important to know about them before you become a homeowner.

“One of the most overlooked and underestimated numbers when buyers actually locate a home and win an offer on it is the tax amount,” said Gelios. “Too many times, I’ve seen real estate agents list what the seller is paying in taxes at that time. If time allows, a home buyer should contact the municipality and ask for a rough estimate as to what the taxes will be if they closed on the home in X month.”

Since taxes almost always increase when homes change ownership, it’s good to get an updated quote before those payments become your responsibility.