Buying an RV is one of the biggest purchases most people will ever make — and one of the easiest ways to get burned. Unlike buying a car, most RVs have dozens of systems that can fail silently, cost thousands to repair, and show no obvious warning signs during a casual walk-through. After 8 years as a professional RV technician, I've seen buyers hand over $40,000 for rigs with frame rot, slideout cable damage, water infiltration, and propane leaks that none of them caught before signing.
This guide will show you exactly how to inspect an RV before you buy — the same way a professional technician does it.
WHY MOST RV BUYERS GET IT WRONG
Most people walk through an RV the same way they'd walk through a house — they look at the layout, check the appliances, flip some switches, and move on. That approach misses 90% of what actually matters. The most expensive problems in an RV are structural and mechanical, not cosmetic. A fresh detail job and new furniture can hide years of deferred maintenance and water damage.
Here's what to actually check:
ROOF & SEALS: THE MOST IMPORTANT INSPECTION
Water is the #1 enemy of every RV. Start on the roof. Look for cracks, bubbling, or separation in the roofing material and around every roof penetration — vents, AC units, antenna mounts, skylights. Any breach in the roof seal leads to water infiltration, and water infiltration leads to rot, mold, and delamination. Press your hand into the ceiling near the walls to feel for soft spots. Check the ceiling corners inside for water staining.
Soft spots anywhere on the floor, walls, or roof deck are red flags — especially near slideouts, windows, and entry doors.
SLIDEOUT SYSTEMS
Extend every slideout fully and watch how it moves. It should move smoothly, stop completely level, and create a tight seal when closed. Listen for grinding or clicking. Uneven movement often points to cable or gear rack issues. Check the slideout seal — it should be continuous and make full contact around the perimeter. Look at the floor where the slide meets the main room for water staining or soft spots.
Slideable room repair is one of the most expensive categories in RV service — cable replacement alone can run $800 to $2,500 depending on the system.
PLUMBING & WATER SYSTEMS
Turn on the water pump and run every faucet, including the shower. Listen for air in the lines (normal if winterized) and watch for leaks under the sink, behind the toilet, and under the bed if there's plumbing access there. Check the water heater — ignite it on both propane and electric. Open the exterior access door and look for corrosion, rust, or prior repairs.
ELECTRICAL & BATTERY SYSTEM
Plug the RV into shore power and check every outlet with a phone charger or simple outlet tester. Test the GFCI outlets. Run the air conditioner, microwave, and any slideout simultaneously to check for breaker sensitivity. Check the battery voltage — 12V batteries should read 12.6V+ when fully charged. Look at the battery terminals for corrosion. Check the converter and inverter if present.
TIRES & RUNNING GEAR
Check tire age — look for the DOT date code on the sidewall. The last four digits indicate the week and year of manufacture. RV tires older than 5 years should be replaced regardless of tread depth. Sidewall cracking is a serious blowout risk. Check lug nut torque visually (look for rust streaks or spinning) and inspect the hitch ball, coupler, and safety chains on towables.
THE TRUTH ABOUT DEALER INSPECTIONS
Dealers have a financial interest in selling the unit — their in-house inspection is not independent and should not be relied upon. Always get a pre-purchase inspection from an independent, certified RV technician before finalizing any purchase over $10,000. A professional inspection costs $300-$500 and can save you tens of thousands.
GET THE FULL INSPECTION TOOLKIT
If you want to do a thorough walk-through yourself before bringing in a tech, our RV Pre-Purchase Inspection Toolkit gives you a 100-point inspection checklist, documentation forms, negotiation scripts, red flag reference guide, and buyer's protection worksheet — everything you need to inspect like a pro and buy with confidence.
Don't let one bad purchase decision cost you years of frustration and thousands in repair bills. Walk in prepared.
Want a Professional RV Tech to Inspect It With You — Or For You?
If you're serious about buying an RV in SE Wisconsin, we offer pre-purchase RV inspections. We'll come to the dealership, seller's lot, or storage facility and give you a full written report on every major system. It's the best $165 you'll spend before writing a check for a $30,000 rig.
Book a Pre-Purchase Inspection → | View Inspection Pricing →
Available throughout Ozaukee, Milwaukee, Waukesha, and Washington counties. Email service@palsbydesign.co to schedule.