The first 90 days after closing: the setup that saves you thousands

The day you close, the house starts running a clock you can't see. Property tax exemption deadlines, insurance grace periods, warranty registration windows, and the slow drip of deferred maintenance all start ticking at once — while you're busy unpacking boxes. The first 90 days aren't about renovating; they're about installing the boring systems that make ownership cheap. Every item below costs less than $200 or nothing at all, and skipping the wrong one costs four figures.

Week one: security and shutoffs

Rekey or replace every exterior lock ($80–200 for a locksmith, less if you swap deadbolts yourself) — the sellers' contractor, dog walker, and cousin all potentially have keys, and your insurance won't care about that nuance after a 'no forced entry' burglary. Then take the single most valuable walk in homeownership: find the main water shutoff, the electrical panel (label the breakers), the gas shutoff, and the water heater's shutoff. When a supply line bursts at 2 a.m., knowing the main valve's location is the difference between a $150 plumber visit and a $15,000 flooded-floor claim. Test the valve now — old gate valves seize, and a shutoff that won't shut is a repair to schedule this month, not discover mid-flood.

1. 1
   Days 1–7: control the house

   Rekey locks, change garage door codes and opener rolling codes, test every smoke and CO detector and replace batteries, locate and test water/gas/electric shutoffs, change the HVAC filter.

2. 2
   Days 8–30: paperwork offense

   File your homestead exemption, confirm escrow is paying taxes and insurance, register appliance warranties, store closing documents and the inspection report in one binder, set up utilities in your name with autopay.

3. 3
   Days 31–60: know your systems

   Service the HVAC if no recent record exists ($100–200), flush or at least inspect the water heater, test the sump pump, walk the roofline and gutters with binoculars after a hard rain.

4. 4
   Days 61–90: build the money layer

   Open a dedicated maintenance savings account and automate 1% of home value per year into it, price-check your homeowners insurance against two competitors, and fix everything flagged 'minor' in your inspection report before it graduates.

The inspection report is your first to-do list

You paid $400–600 for a professional to catalog everything wrong with the house, and most buyers read it once, negotiate, and never open it again. Reread it in month one. Every 'minor' item — the slow drain, the missing flashing, the negative grading by the back door — is a cheap fix now and an expensive one after a year of water finds it. Sort the list into do-now (water-related, safety), this-season, and monitor, and put the first category on the calendar.

The money moves people miss

• File the homestead exemption immediately — in many states it cuts hundreds to thousands off annual property taxes and is not automatic.
• Audit your first escrow statement: lenders regularly over- or under-estimate taxes on a home that just changed hands, and a reassessment after your purchase can spike next year's payment. Budget for the adjustment now.
• Keep every receipt for improvements in the binder — capital improvements raise your cost basis and can cut capital gains tax when you sell decades from now.
• Photograph every room, serial numbers of major appliances, and the electrical panel — a 30-minute video walkthrough is the insurance-claim documentation you'll wish you had after a fire or theft.
• Meet the neighbors on both sides in month one. Free surveillance, free lore about the house ('the basement got water in 2019'), and the relationship you'll need before any fence conversation.

What the first quarter costs — and returns

The checklist also has a sequencing logic worth respecting: security and shutoffs come first because their risks are immediate and their fixes are same-day; paperwork comes second because exemption and warranty windows close on the calendar, not on your schedule; systems knowledge comes third because you want a baseline before the first season change stresses everything; and the money layer comes last only because it needs the first month's information — what the systems are, how old they are, what the inspection flagged — to be set at the right level rather than a generic one.

One more first-quarter habit that pays for a decade: write down everything you learn about the house while it is fresh. Which breaker controls the garage, where the irrigation valves hide, what the seller said about the roof, which paint colors are on which walls. Sellers hand over keys, not knowledge, and the details you absorb in the first 90 days — then forget by year three — are exactly the ones you will pay a contractor an hour of diagnostic time to rediscover. A shared note on your phone, added to whenever the house teaches you something, becomes the operating manual the house never came with.

The bottom line

The first 90 days set the cost curve for the next decade. Rekey and label, find and test the shutoffs, file the exemption, reread the inspection report, automate the maintenance fund, and put the boring recurring tasks on a calendar. None of it is glamorous, all of it is cheap, and together it converts the scariest purchase of your life into a machine that mostly just needs its filters changed.