The first few months in a new home feel great, and they're also when a lot of new owners make choices they regret later. Some cost money right away. Others quietly make it harder to refinance, sell or tap your equity years from now.

Here are five common mistakes first-time homeowners make after moving in, plus a few California-specific steps that protect both the house and your future options. Most of them apply just as much if you've owned before and just moved up.

1. Not changing the locks

You have no idea how many keys to your new home are out there: past owners, contractors, dog walkers, neighbors. Rekey or replace exterior locks in the first week, and reset garage door codes, smart locks, alarm codes and Wi-Fi passwords on any devices that came with the house.

While you're at it, handle the paperwork that's easy to forget. Save your closing documents somewhere safe, set up your property tax payments if they aren't in an impound account, and file for the homeowners' exemption with your county assessor. Then set money aside for the supplemental tax bill, which usually arrives a few months after you close. More on the hidden costs of homeownership.

2. Not learning how the house works

When something goes wrong, the first five minutes matter. Before you need them, find and label:

• the main water shutoff, and the shutoffs under sinks and toilets

• the gas shutoff, with the right wrench stored nearby in case of an earthquake

• the electrical panel, with each breaker labeled

• the sewer cleanout outside the house

Check that the water heater is strapped, that smoke and carbon monoxide alarms work and that you know when the furnace filter was last changed. Your inspection report is a ready-made maintenance list, so go back through it now that you live there. Here's how long major appliances and systems usually last.

3. Painting everything right away

It's tempting to repaint before the boxes are unpacked. Living in the space for a few weeks first usually leads to better choices. You'll see how the light changes through the day and how you actually use each room.

Painting first can also hide things you'd want to see, like hairline cracks that are still moving or a ceiling stain that comes back after the first rain. If the home was built before 1978, assume older paint layers may contain lead and follow lead-safe practices before sanding or scraping.

4. Impulse purchases and new debt

Right after closing, a lot of new owners feel flush: new furniture, new appliances, maybe a new car. Spending your cushion is one risk. The bigger one is debt that limits your options later.

• Your future refinance gets underwritten much like your purchase. If car loans and store credit push your debt-to-income ratio too high, a refinance you'd qualify for today could be declined later.

• Watch for liens dressed up as programs. Solar panels, windows and other upgrades financed through your property tax bill can put a lien on your home. They're often pitched as painless monthly savings, and that lien can complicate a refinance or a sale. Read the terms before you sign anything at your door.

• Keep an emergency fund. Something will break in the first year.

Buy the essentials first: a bed, somewhere to sit, a table. Let the rest come as you learn the space.

5. Rushing into renovations without a plan

Big projects go better with time, a budget and the right paperwork:

• Get permits for anything structural, electrical, plumbing or that adds living space. Unpermitted work can cause trouble with insurance, appraisals and a future sale. Here's why unpermitted work matters.

• Check that any contractor is licensed with the California Contractors State License Board before you hire them.

• Get several bids and keep 10% to 20% in reserve for surprises.

• If you're considering an accessory dwelling unit, learn the local rules first. See what an ADU is and how it works.

If you plan to borrow against your home for a project, think through the timing and the payment before you start. More on using your home equity carefully.

What to do next

Spend your first month on security, systems and paperwork, and your first year learning the house before you make big changes or take on new debt. For a fuller checklist, see things to do after closing. Thinking about your next move? You can search homes across the East Bay anytime.

Questions about your loan, equity or a future refinance? Call or text 925-876-0876, or reach us here.

Pacific Residential Partners | NMLS #633518 | DRE #02101650