You have steady income, a decent credit score and a down payment saved. You got preapproved. Then, days before closing, the lender says no.

It happens, and often the cause isn't a big financial problem. It's a small move made at the wrong time. Here are seven of the most avoidable ones.

1. Changing jobs mid-process

A new job, even one that pays more, can reset how a lender views your income. Moving from a salaried role to commission, contract or self-employed work is the bigger risk, because lenders typically want a track record of that kind of income before they count it.

It can happen even after you sign. Brian Mix, a loan officer and founder of ReadinessIQ (NMLS #111175), remembers a hard-won refinance: the borrower signed his closing documents on a Friday, then quit his job the following Monday without telling anyone.

"When our funding department completed its final verbal verification of employment, his employer confirmed he'd resigned, and we couldn't fund the loan," Mix says. When Mix reached him on vacation and asked if he had a job to go back to, the borrower's answer was: "How do you know about that?"

"Never assume signing your closing documents means your mortgage has funded," Mix says. "If you're considering quitting or changing jobs, speak with your loan officer before making the move, and understand that employment may be verified again before funding."

What to do: If a job change is coming, tell your loan officer before you accept, not after, and that includes the days between signing and funding.

2. Unexplained deposits

A large deposit that doesn't match your paycheck gets flagged. Lenders need to know the money isn't a hidden loan. A cash gift from family, money from selling a car or a transfer between your own accounts can all hold up approval if there's no paper trail.

What to do: Keep records for any non-payroll deposit, and get a signed gift letter for family help.

3. Opening new credit before closing

Financing furniture, a car or a store card to grab a checkout discount adds a new inquiry and a new monthly payment. Lenders often re-check credit right before closing, and a new payment can push your debt-to-income ratio past the limit.

Nathan Young, founder and mortgage broker at North Star Mortgage Network (NMLS #325206), had a buyer who was approved, had the appraisal in and was five days from closing. Then he financed a truck "because the dealer said it wouldn't matter."

"The new payment pushed his debt-to-income over the limit, and we had to restructure the loan and push closing," Young says. His advice: "Don't open credit, buy furniture or cars, or change jobs until after you close, and call your loan officer before any big money move."

What to do: Treat your credit as frozen from application to closing.

4. Co-signing someone else's loan

Co-signing a sibling's car loan or a child's student loan makes that debt yours as far as a lender is concerned, even if you've never made a payment on it.

What to do: List every loan you've co-signed up front so your loan officer can plan for it.

5. Closing old credit cards

Closing cards you don't use feels responsible, but it can shrink your available credit and shorten your credit history, both of which can lower your score at exactly the wrong moment.

What to do: Leave old accounts open until after closing unless your loan officer says otherwise.

6. A forgotten bill in collections

A small medical bill, an old utility balance or a gym fee you disputed years ago can show up as a collection account and surprise you during underwriting.

What to do: Pull your credit reports from all three bureaus at AnnualCreditReport.com before you apply and clear up errors early.

7. Spending down your savings

Your down payment isn't the only money a lender looks at. Many loans also consider cash reserves left over after closing. Draining savings on moving costs, new appliances or a vacation can leave you short.

What to do: Ask your loan officer how much needs to stay in the bank through closing, and don't touch it.

The bottom line

Many last-minute problems come down to timing. From application to closing, keep your job, credit and bank accounts as steady as possible, and ask your loan officer before making any financial move.

This article is for educational purposes only and isn't financial advice. Loan requirements vary by lender and loan program.

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