As an NRVIA Certified RV Inspector, I've walked through hundreds of used RVs — and I can tell you that the ones that look the best on the outside aren't always the best buys. Conversely, some of the best-value RVs I've ever seen didn't photograph well but were mechanically sound and well-maintained. Here are the ten most important things to check before you buy.
1. The Roof — First, Always
Water intrusion is the number one killer of used RVs. Before you look at anything else, get up on the roof (if you can safely do so) and check the condition of all sealant around vents, air conditioners, antennas, and seams. Cracked, peeling, or missing sealant is a red flag. Look for soft spots anywhere on the roof surface — a spongy feel underfoot means water has already gotten in.
2. All Four Corners — Interior and Exterior
Water almost always enters at the corners. Check the interior corners of every slide, every window frame, and every exterior door frame. Look for bubbling, discoloration, soft paneling, or delamination of the interior walls. Outside, look for separation between the sidewall and roof line.
3. Slide-Out Condition and Seals
Run every slide in and out at least three times. It should move smoothly, seal completely when retracted, and not leave any gaps. Check the rubber seals around the entire perimeter of each slide — they dry out and crack over time. Replacing slide seals isn't catastrophic, but it's a negotiating point.
Pro tip: Have someone stand outside while you're inside running the slides. They can watch for any uneven movement, grinding, or misalignment that's easy to miss from inside.
4. Electrical System — 12V and 120V
Test every outlet, every light switch, every 12V outlet, and every USB port. Bring a simple outlet tester — they cost a few dollars and tell you immediately if an outlet is wired incorrectly. Check that the converter/charger is functioning by plugging in shore power and confirming the batteries are charging.
5. Propane System
Turn on the propane and test every burner on the range, the oven, the furnace, and the water heater (if propane). Check around the connections with soapy water or a leak detector for any bubbling. The regulator should be dated — most manufacturers recommend replacement every 10–15 years.
6. Freshwater System
Fill the freshwater tank and run the pump. Check every faucet, both hot and cold, and confirm the pump cycles normally — it should prime, pressurize, and shut off cleanly. Look under every sink for any signs of previous leaks. Check the water heater for rust or calcium buildup around the drain plug.
7. Waste Systems
Ask when the black and gray tanks were last flushed and treated. Check the dump valves — they should open and close smoothly. A sticky or leaking dump valve is a common and relatively inexpensive fix, but it's worth noting.
8. Tires and Wheels
RV tires age out before they wear out. Check the DOT date code on the sidewall — it's a four-digit code showing the week and year of manufacture. Most RV tire manufacturers recommend replacement at 5–7 years regardless of tread depth. Old tires on an otherwise solid RV are a safety issue and a negotiating point.
9. Chassis and Frame (Motorhomes)
For motorhomes, check the engine oil, transmission fluid, coolant, and power steering fluid. Look for any leaks under the engine compartment. Start the engine cold and listen for any unusual sounds during warm-up. Check brake function carefully on a test drive. For diesel pushers, ask for any recent service records.
10. Appliances — All of Them
Run the air conditioner on cooling mode. Run the furnace. Run the refrigerator in both AC and propane mode. Run the microwave. Test the entertainment system. Test any awnings. Every one of these has value — and every one that doesn't work is either a repair cost or a negotiating chip.
The Bottom Line on Used RV Inspections
A pre-purchase inspection by a certified NRVIA inspector costs a few hundred dollars and can save you thousands. I've seen buyers walk away from deals that looked great until inspection — and I've seen buyers get exceptional value on units that others passed over because they didn't look as shiny on the surface. Never skip the inspection.