How to Inspect a Used RV in 30 Minutes Before You Bid
Here is how to inspect a used RV at an auction preview: work from the roof down. Seams and sealant first, then floors and walls for water damage, then slides, plumbing, generator, tires, chassis and running gear. You usually get a few hours in a gravel lot with no hookups, no test drive and a crowd looking at the same units, so the order matters as much as the list. This guide covers the 30 minutes that count and how to turn what you find into a max bid you will not go over.
What to bring and how to order the walk
Pack a bright flashlight, a moisture meter (a pinless model is easier to use on a rig you do not own yet), a small step ladder or a camera on a pole for the roof (some yards do not allow climbing on the units), a screwdriver, gloves, a tread gauge and your phone for photos. Add a multimeter if the yard has power.
Work top to bottom, saving the chassis for last. Before you start, photograph the VIN plate and the certification label near the entry door, confirm the VIN matches the lot listing, and check the lot terms for whether the title is clean, salvage or rebuilt; a salvage or rebuilt title changes what the rig is worth and may limit financing and insurance.
Most repo and surplus lots sell as-is. Our guide on how to buy an RV at auction covers registration, deposits and payment.
Roof and seals first
Water is what kills RVs, and most of it gets in from above or through failed seals: roof seams, window frames and slide seals. If you can safely see the roof, check the front and rear caps, the roof-to-sidewall edges and the sealant around vents, skylights and the air conditioner. Sealant that is cracked, lifted, chalky or missing has failed or is about to, and any of those spots may already be letting water in.
On rubber (EPDM or TPO) roofs, look for tears, bubbles and soft spots under your palm; flex between rafters may mean wet decking. If you cannot reach the roof, look from the ground for streaks running down from seams and staining under the front cap.
Water intrusion: floors, walls, stains and smell
A musty smell at the door usually means wet wood. Walk the floor slowly, weighting every step: inside the entry door, around the shower and toilet, under the slide edges, in the rear corners and along the exterior walls. Soft or spongy spots usually mean a rotten or delaminated subfloor.
Check cabinet corners and the ceiling around vents for brown rings, bubbled wallpaper, dark seams and screws with rust halos. If staff allow it, check with the moisture meter at the wall bottoms below windows, the front corners over the cab, and around each slide; a pinless meter avoids leaving holes in a rig you do not own yet.
Outside, sight down each sidewall. Fiberglass that ripples or bubbles is delamination: the outer skin has separated from the substrate, usually because of water, sometimes because the factory adhesive bond failed. It is expensive to fix.
Slides, plumbing and the water heater
Ask staff to run the slides if power is available. Watch for uneven travel, grinding and a room that racks or stops short, and inspect the wiper and bulb seals at each opening; cracked or flattened seals are likely to leak.
Plumbing is hard to test without hookups, but open every cabinet with a water line and look for staining, mineral crust and swollen particle board. Pull the water heater door and look for a rusted tank, a crumbling burner or pink antifreeze residue, a sign it was winterized and maybe never flushed.
Generator, house batteries and shore power
Photograph the generator hour meter. Low hours on an older set is not automatically good; generators that sit often develop fuel problems, especially gasoline sets with stale fuel in the carburetor. Look for oil leaks and listen for surging if it runs.
In the battery compartment, bulging cases, white corrosion and a rotted tray are signs of neglect. Units from repo auctions often arrive with dead or missing batteries; plan on replacing them.
If the yard has a 30- or 50-amp outlet and staff allow it, plug in, confirm the converter is charging (roughly 13 to 14.5 volts at the battery terminals) and test the outlets, air conditioner, microwave and refrigerator.
Tires by DOT date, chassis rust and frame
RV tires age out long before they wear out. The last four digits of the DOT code on each sidewall give the week and year: 2319 is the 23rd week of 2019. Tire makers generally call for an annual inspection after five years and replacement at ten years regardless of tread, and many RV shops recommend replacing RV tires at five to seven years. Check every tire, spare and inside duals included, for sidewall cracking and flat spots.
Get under the rig. Surface rust on a steel frame is normal; flaking scale, holes and rust-through are not, especially at outriggers, hitch or receiver, spring hangers and wherever road salt collects.
Running gear: engine and transmission, or axles and brakes
On a motorhome, pull the dipsticks. Milky oil, burnt-smelling transmission fluid and rusty or oily coolant are all warnings. If the auction starts it, watch the exhaust once the engine has warmed up for blue smoke or white smoke that does not clear, listen for knocks, and check that the dash warning lights clear. Most yards will not let you drive; price any drivetrain you cannot hear as an unknown.
On a travel trailer or fifth wheel, look at the inside of each wheel and the back of each hub for slung grease, and at the dust caps for dents or missing caps, which point to bearing trouble. You cannot check bearing play with the tire on the ground, so treat the bearings as an unknown unless the auction lets you lift a wheel. Check the brake wiring behind each wheel, the breakaway switch and cable, and the spring hangers for cracks. On a travel trailer, check the coupler latch, the safety chains and the A-frame welds; on a fifth wheel, check the kingpin, the pin box and the bolts that hold it to the frame. Sight down the frame rails for a sag or kink.
How to inspect a used RV when you cannot attend the preview
Ask the auction house for photos of specific spots: roof seams, floor under the slides, water heater bay, DOT codes. Some remarketers post condition reports or walk-around video and will answer written questions; others sell strictly from the listing photos and will not. Preview policies differ by platform; check the source page for the seller.
For a rig you are serious about, hire a certified RV inspector to attend in your place, after confirming the auction allows third-party inspectors and what access they get; without hookups, even a pro is limited to the same visual checks described above. The NRVIA keeps a directory; the fee varies by region but is far less than one bad roof. If bidding blind, assume the worst about anything you cannot verify and treat salvage lots as project rigs until proven otherwise.
Turning findings into a repair budget and a lower max bid
Sort findings into three buckets. Routine: batteries, tires, sealant, a water pump. Structural: soft floors, delamination, a rotted roof deck, rust-through on the frame. Unknowns: an engine never started, plumbing never pressurized, a generator that would not run.
Price routine items at retail parts plus shop labor unless you will do the work yourself. Floor and roof rebuilds commonly run into the thousands and can exceed what an older rig is worth, which is usually a reason to pass. Put a real dollar number on each unknown, because the auction will not.
Then work backward. Start from what comparable rigs actually sold for; RVBidFind Pro shows a comp value and all-in estimate on every lot. Subtract your repair total, a cushion and what lands on top of the hammer: buyer premium (typically 10 to 15 percent on commercial platforms, none on eBay vehicles and most government surplus), sales tax, documentation fees and transport. What remains is your max bid. Write it down before bidding opens and do not move it.
Questions
What is the most important thing to check when inspecting a used RV?
Water damage. Check roof seams and sealant, walk the floor for soft spots, look for stains in cabinet corners and around slides, and sight down the sidewalls for delamination. Almost everything else is cheaper to fix than a wet structure.
How do I read the DOT date code on RV tires?
Read the last four digits of the DOT code on the sidewall: the first two are the week and the last two are the year, so 3618 means the 36th week of 2018. Tire makers generally say to replace tires at ten years regardless of tread and to inspect them yearly after five; many RV shops recommend replacing RV tires at five to seven years.
What if I cannot attend the auction preview in person?
Ask the auction house for photos or video of roof seams, floors and the water heater bay, and hire a certified RV inspector or mobile RV tech to attend for you. If you must bid blind, assume the worst about anything you cannot confirm and lower your max bid to match.