Before the house hunt, do the homework.

When you start thinking about buying a home, it’s natural to focus on one big number: the down payment. But the down payment only gets you through the door. Once you’re inside, a home comes with a steady stream of costs. Some arrive every month, some once or twice a year and some show up without warning.

The good news is that most of these costs are predictable if you look for them early. A little homework now can help you choose a price range you’re comfortable with, instead of one that stretches you thin.

Start with the full monthly payment

Your monthly mortgage payment is usually more than the loan itself. The four basic parts are often called PITI, short for principal, interest, taxes and insurance.

• Principal is the part of each payment that pays down the amount you borrowed.
• Interest is what the lender charges you to borrow that money.
• Property taxes are set by local governments, usually at the county level, based on the value of the home.
• Homeowners insurance pays for losses and damage from events like a fire or burglary. Lenders generally require it.

Depending on the home and the loan, you may have more to add:

• Mortgage insurance. If your down payment is less than 20% of the price, you’ll likely pay for mortgage insurance. It protects the lender, not you, if you fall behind on payments.
• Homeowners association (HOA) dues. If the home is in a community with an HOA, these fees help pay for common areas and amenities. They can rise over time, too.
• Extra insurance. Standard homeowners policies generally don’t cover floods. If the home is in a FEMA-designated Special Flood Hazard Area, you’re likely required to buy flood insurance.

Many homeowners pay their property taxes and insurance through an escrow account. Your lender collects a share with each monthly payment, then pays those bills for you when they’re due. That spares you a large bill all at once. Taxes and insurance premiums change over time, though, and the escrow amount is adjusted each year. So your total payment can change even if your interest rate doesn’t.

Budget for costs your lender won’t bill you for

Some of the biggest costs of owning never appear on your mortgage statement.

Utilities

Electricity, gas, water, sewer and internet all add up. If you rent now, some of these may be new to you. They can vary a lot depending on local rates, the climate and the home’s size and energy efficiency. It’s fair to ask the seller or your agent what the home’s bills have typically been.

Maintenance and repairs

Every home needs care, from small jobs that keep things running to larger repairs when something wears out. There’s no single right number to set aside. A practical approach is to choose a fixed amount to save each month in a separate account, then adjust it once you know the home’s age and condition.

A home inspection, which the buyer usually pays for, can tell you about the home’s condition and any likely maintenance issues before you commit. Use what you learn to plan ahead for the bigger items.

Add up the upfront costs

Before you get the keys, expect several one-time costs:

1. Down payment. The share of the price you pay up front. Many loan options let qualified buyers put down much less than 20%.
2. Earnest money. A good-faith deposit you submit with your offer to show the seller you’re serious. At closing, it can be applied toward your down payment or closing costs.
3. Closing costs. Fees paid to your lender and the other parties who help complete the loan and the sale. The Consumer Financial Protection Bureau (CFPB) says these typically range from 2% to 5% of the purchase price, not counting your down payment. Your actual costs depend on the loan, the home and the location.
4. Inspection. The fee for the home inspector.
5. Moving. Professional movers or a rental truck, plus the small costs that come with any move.
6. Early repairs and furnishings. Fixes, renovations or furniture you’ll want soon after you move in.

Keep a cushion after closing

Here’s a step that’s easy to skip: don’t spend every dollar you’ve saved to get the house. The CFPB suggests a simple order of operations. Start with your total savings. Set aside money for moving, renovations, furnishings, other goals and an emergency cushion, which is usually three to six months of expenses. What’s left is the most you have for closing. Subtract your estimated closing costs, and the remainder is your maximum down payment.

That emergency cushion matters even more once you own. When something breaks, the repair is yours to handle and pay for.

It also helps to leave room in every number. At this stage, none of your estimates is exact. A little slack means a higher-than-expected bill won’t leave you scrambling.

Your next step

Write down what you pay for housing today, including rent and utilities. Next to it, list each cost from this tip: principal and interest, property taxes, homeowners insurance, mortgage insurance, HOA dues, utilities and a monthly maintenance set-aside. Pencil in a rough guess for each one. You don’t need exact figures yet. Seeing the full picture in one place is the homework that makes the house hunt calmer.