Start With the Exterior and Roof

The exterior skin and roof are where an RV's biggest structural problems tend to show up first, and they are also the easiest place to start an inspection because you do not need any tools.

Walk the full exterior in direct sunlight and look at the sidewalls from a low, raking angle rather than straight on. Waves, bubbles or creases in the fiberglass or aluminum skin are classic signs of delamination, where the outer skin has separated from the wall's inner structure. Press on any suspect area: a spot that feels spongy or soft, or that sounds hollow when you tap it, points to delamination or water-softened backing material underneath. Pay extra attention around windows, doors and any roof-to-wall seams, since those are common entry points for the moisture that causes delamination in the first place.

On the roof itself, inspect every seam, vent, skylight and air conditioner mount for the sealant that keeps water out. Lap sealant that has cracked, alligatored or started to peel is a signal that a reseal is due; the process manufacturers describe generally involves cleaning off the old sealant with a solvent like mineral spirits before applying fresh sealant, so a roof with peeling seals is not necessarily a dealbreaker if it has not been neglected for years. If the RV has a rubber or EPDM roof membrane, ask when it was last cleaned. Roofing manufacturer Dicor recommends cleaning these roofs at least four times a year with a mild, non-abrasive cleaner and a medium-bristle brush; a roof that is visibly chalky, grimy or covered in tree debris suggests upkeep has lapsed. As a general habit, plan to inspect the roof seasonally, in spring and fall, and again after any hail or high-wind event, rather than relying on a fixed day count.

If you can safely access the roof, walk it slowly (or have the seller/dealer do it) and check that vents, antennas and AC shrouds are secure and that there is no soft or spongy decking underfoot.

Check for Interior Water Damage

Water damage often shows up inside the RV before it is obvious outside, so treat the interior walkthrough as a continuation of the roof and seal inspection rather than a separate step.

Look for water stains or discoloration on ceilings, walls and around windows. Wallpaper or wall-panel laminate that has started to ripple, bubble or pucker is a strong indicator of moisture trapped behind the surface. A musty or mildew smell, even in an otherwise clean-looking unit, can mean there is hidden water intrusion or mold that has not yet reached the visible surface. Run your hand along the lower walls, the areas under windows and the corners near the roofline, feeling for soft spots or unusual give in the wall material.

Check under sinks, around the toilet base, under the refrigerator and in any exterior storage bays for staining, corrosion or a lingering damp smell. Pull back removable interior panels near plumbing runs if the seller allows it. None of these checks require special tools, just a flashlight and a willingness to get your hands on every surface rather than doing a quick visual pass from the doorway.

Read the Tires: DOT Date Codes and Replacement Guidance

Tires are one of the few RV components with a built-in, easy-to-read manufacturing date, and checking it takes less than a minute per tire.

Every tire made after 2000 carries a four-digit DOT date code on the sidewall: the first two digits are the week of manufacture and the last two are the year. A code reading "2516," for example, means the tire was built in the 25th week of 2016. Tires made before 2000 used a three-digit code and are ambiguous about which decade they come from, which is itself a reason to be cautious of any tire without a clear four-digit code.

Tire age matters more than tread depth on an RV, since many units sit for long stretches between trips and the rubber degrades from age and UV exposure even when tread looks fine. There is no single federal mandate on replacement age; the National Highway Traffic Safety Administration defers to vehicle and tire manufacturers on this point. In practice, guidance varies by manufacturer, ranging from around six years for some vehicle makers to as long as ten years for some tire makers, with most guidance also recommending closer annual inspection once a tire passes the five-year mark regardless of the eventual replacement date. Rather than treating any single number as a hard rule, check the date code on all tires, including the spare, and weigh it against that range when you are deciding whether tires need to be part of your negotiation.

While you are down at wheel level, look for cracking in the sidewall grooves and uneven wear patterns that could point to alignment or suspension issues. Also check for mismatched tire brands or sizes across the axle, which can indicate a prior blowout replacement done in a hurry.

Inspect the Frame, Suspension and Wheel Bearings

The chassis underneath an RV rarely gets the same attention as the living space, but problems here are some of the most expensive to fix after purchase.

Get underneath the unit, or have it put on a lift if the seller allows it, and inspect the frame rails, cross-members, wheel wells, suspension mounts and weld joints for rust, cracked welds or signs of prior repair. A hammer-tap test on any suspicious rust spot can help: a hollow sound or flaking metal suggests the rust has compromised the material rather than just sitting on the surface. Compare welds on the left and right sides of the frame; mismatched welds are a common sign that one side has been repaired or reinforced after a prior incident.

For towable RVs, ask about the wheel bearing service history. Axle manufacturers commonly recommend inspecting and repacking wheel bearings roughly once a year or every 12,000 miles, whichever comes first, though the exact figure varies by axle brand and model, so check the axle's own tag or manual rather than assuming a single number applies. If the seller cannot produce any bearing service records and the unit has significant mileage, budget for a bearing inspection soon after purchase regardless of what the axle tag says.

While underneath, also check brake lines and connections for corrosion or wear, and have a technician verify brake function as part of a pre-purchase inspection if you are not confident evaluating it yourself.

Test the Propane System

Propane issues are a safety matter first and a maintenance matter second, so this section is worth doing carefully rather than quickly.

Start with the cylinder or tank itself. Federal regulation sets the standard requalification interval for propane cylinders at five years, with a longer twelve-year interval available for externally protected cylinders in non-corrosive LPG service that pass a volumetric expansion test, followed by ten-year proof-pressure retest cycles after that. It is illegal to refill a cylinder past its requalification date, so check the stamped date on the collar before assuming the tank is usable as-is.

To check for leaks, apply a soap-and-water solution, without chlorine or ammonia additives, to the tank valve, regulator, pigtail hoses and every fitting along the line, then watch for continuous bubbling, which indicates a leak. A manometer test is the more rigorous version of this check and is something a professional or NRVIA-certified inspector can perform if you want a definitive read before closing.

Ask about the age of the pigtail hoses and regulator. These are wear items: hoses are commonly replaced somewhere in the five-to-ten-year range due to UV and vibration wear, and regulators commonly last on the order of ten to fifteen years, though neither figure is fixed and both should be treated as general ranges rather than a countdown clock. Also check the printed expiration date on any onboard CO or LP gas detector; sensors degrade over time, and manufacturers commonly rate CO and LP detectors somewhere in the five-to-seven-year range, with some rated closer to ten. Replace by the date printed on the unit, not by how long you personally have owned the RV.

If the RV has a generator you plan to test during the inspection, only run it outdoors, and keep it more than 20 feet from windows, doors and vents per CDC guidance, with a battery-powered CO detector on hand while it runs.

Check the Electrical System and Shore Power

Electrical problems are often intermittent, so this is one area where a slow, deliberate check during inspection matters more than a quick glance.

Examine the shore power cord end to end for damage, exposed wire or burnt or discolored prongs. Plug in and listen to the converter as it charges the house batteries; it should run with a quiet hum, and a loud buzzing sound is a sign something is wrong. Test every GFCI outlet using its built-in test button, and use a household outlet tester on both 12-volt and 120-volt circuits throughout the RV. Open the breaker panel and look for clear labeling along with any heat discoloration around the breakers themselves, which can point to a past overload.

Cycle interior and exterior lights, slide-out and awning switches, and any powered vents while the unit is on shore power, then repeat what you can while running on battery alone to see whether anything behaves differently between the two power sources.

Test the Slide-Outs and Appliances

Slide-outs combine mechanical, electrical and seal components in one system, so they deserve a slower look than most buyers give them.

Before operating a slide, confirm the house battery is fully charged and check for any blown fuses; slide mechanisms will not move correctly on a weak battery, which can look like a mechanical fault when it is really a power issue. Inspect the slide seals for wear or any sign they have been dislodged by repeated slide movement, and look at the rollers and rails for rust or built-up debris. Lubrication needs depend on the mechanism: some in-wall slide systems need no lubrication at all, while hydraulic rack-and-pinion slide systems need periodic lubrication and can rust and seize if that maintenance has been skipped.

Cycle every slide in and out at least once, and watch and listen for grinding, uneven movement or a slide that stops short of fully closing.

For appliances, run the refrigerator on both shore power and propane if it is a dual-mode unit, run the furnace and air conditioner long enough to confirm they cycle normally, and run the water heater until it produces hot water. None of these checks require special equipment, just enough time on-site to let each appliance complete a full cycle rather than switching it on and off in a few seconds.

Verify the Title, VIN and Valuation

The paperwork side of an RV purchase deserves the same scrutiny as the mechanical side, especially on a used unit changing hands privately.

Run the VIN through NICB VINCheck, a free public tool that flags vehicles reported stolen and unrecovered or declared a total loss or salvage by participating insurers. It is a useful first screen, but it does not cover accident history, prior sales or open recalls, so treat a clean VINCheck result as one data point rather than a full history report. Confirm the VIN on the title matches the VIN plate on the RV itself, and make sure the seller's name on the title matches the person you are dealing with.

For a sense of fair market value, use an independent RV valuation guide. The tool long known as NADAguides has since been absorbed into J.D. Power's specialty valuation service, so search for the current unit under that name if an older bookmark or app no longer works. Pull a valuation range for the specific year, make, model and floor plan rather than a generic model-line estimate, since options and condition swing RV values more than they do for cars.

When to Bring in a Certified Inspector

A thorough buyer walkthrough will catch a lot, but some systems genuinely benefit from a trained third party, particularly on a higher-value purchase.

The National RV Inspectors Association (NRVIA) certifies and lists independent RV inspectors. Certified inspectors complete a training program covering DC and AC electrical systems, propane, plumbing, refrigerators, air conditioning, water heaters and furnaces, and must pass an exam; ongoing membership requires annual dues, continuing education and adherence to a standards-of-practice and code-of-ethics framework. Worth noting: NRVIA itself does not warrant the quality of any individual inspection, so an NRVIA credential tells you the inspector met a training bar, not that every inspection outcome is guaranteed.

A pro is especially worth it when you are buying sight unseen, buying a much larger or more complex unit than you have owned before, or when your own walkthrough turns up one or two issues and you want a full diagnostic before deciding whether to walk away or negotiate. If you are still weighing whether a new or used unit makes more sense for your budget and timeline in the first place, our new-vs-used RV buying guide walks through that decision in more detail, and our rundown of common first-time buyer mistakes covers pitfalls that show up after the sale rather than during it.

Whatever you find during inspection, weigh it against the full picture of what RV ownership costs over time, not just the purchase price; our guide to the true cost of RV ownership is a useful reference for budgeting repairs alongside routine expenses.

Frequently Asked Questions

Can I still do a pre-purchase inspection on a dealer unit that's on a prep or delivery hold? Yes, and it is worth asking for regardless of hold status. Ask the dealer to schedule your walkthrough, or a third-party inspection, before the unit goes through final prep so any issues you find can be addressed as part of that process rather than after you take delivery.

What if the seller won't let me run the generator, slides or appliances during inspection? Treat that as a reason to slow down, not a reason to skip the check. A seller with nothing to hide typically has no issue with a buyer running every system through a full cycle. If access is limited to a private sale where the seller genuinely cannot demonstrate a system, factor the unknown into your offer or make the sale contingent on a follow-up test.

Does a rental-return or fleet RV need a different inspection approach than a private-sale unit? The same checklist applies, but pay closer attention to wear items that scale with heavy, varied use, such as slide seals, tire condition and appliance cycling, since fleet units typically see more operating hours across more drivers than a privately owned RV of the same age.

Should I attend a professional NRVIA inspection in person? If your schedule allows it, yes. Being present lets the inspector walk you through findings in real time and show you exactly what a flagged issue looks like, which is harder to absorb from a written report alone. Confirm the format and expected time commitment directly with your chosen inspector, since it varies by unit size and inspector.