In spite of all the help you may get here, there will always be something you forgot to ask. Owner's Briefcase.....most coaches come with a rather sizeable "satchel" of manufacturer's owner's manuals/installation manuals. If such information is not available, you're operating at a serious handicap. If you don't have such with your coach, you almost need to tape or video the walkthru because it is ALL that you have. If you don't get that, I'd begin to "collect" as much of it as possible from off the internet and then ask "owners" if you can borrow/copy theirs. There is a lot of "maintenance" information in that material as well as "how to use" information. This is of particular importance when it comes to the engine/transmission and chassis maintenance. I would be inquiring about any guarantee/warranty offered by the selling dealer also. How long? What's covered? I'd think a reputable seller would stand behind most onboard systems for 30 days at a minimum. Where practical, you need to ask the person conducting the walk-thru to "demonstrate" the operation of the systems, not just say, "do this, then do this" Act dumb, make them show you, not tell you. Something I forgot to ask when I bought mine, and got burned on, was the 110v heating element in the water heater. Worked great on gas, but electric element was burned out. Not sure how you verify this unless there is a system monitor on-board that will show "amps" being drawn on 110v shore power. Mine had that very system, but I still never asked about the water heater element. Fridge is a similar situation, should work on both 110 and propane. Air conditioning...mine works but is not overly impressive in cooling capability. Hoping it's low on refrigerant and I can get a bit more "cool" out of it.
My engine was supposedly serviced, but upon close inspection, the oil filter, fuel filter, and water separator all seemed to be heavily laden with dirt leading me to believe that they had not been serviced. Be nosy, ask questions about dealer servicing of engine/transmission/chassis and related systems. I replaced all filters on mine just to be safe. Diesel air filters are high dollar items, I'd make sure it was replaced..we're talking 140 or so dollars. Tires....definitely look at the date codes, if they are approaching 7 yr in age, then
regardless of looks, they are becoming a definite "risk" to happy motoring. Most folks change them at 7 years or so because you don't want a blowout on the highway. Aside from the inconvenience it causes, sometimes they do physical damage to the coach body. You can google DOT tire code and get more than you want to know about tires.
Another area that I didn't notice or ask about was the condition of the slide topper. That is the rollout awning that covers the slide top. Upon close inspection after I "owned" it, I found one of them to be in very poor condition....torn. It was one of those things that I could have "visually" checked, but I never thought about it. Same thing goes for the awning that provides shade. Have them demo its deployment and retraction and take a good look "through" it for pinholes, tears, etc. I'd want them to demo slide extension/retraction too. Leveling jacks, make sure they all work and retract as they should. They are deployed "hydraulically" but are retracted by springs. Make sure, when extended that the normally hidden surfaces are shiny and free of any rust. If they look rusty or "hang up" when being retracted by the springs, you're looking at considerable expense. Not all systems work the same and not all systems are straightforward in operation. Pay close attention to how your system works.
Generator. I'd make sure it starts and runs under a heavy load like the A/C. Water pump....when hooked to city water, the water pump isn't needed, but when you are not, it is the means of getting water everywhere in the coach. Make sure it works and shuts off. That means, make sure it delivers water to the faucets and make sure that when the faucet is off, the pump shuts off. These pumps operate on the sensed pressure between the pump and your faucets/toilet/etc. The pump runs a few seconds after the faucet is closed and then shuts down on pressure. If it continues to run, you have a leak, or the pump is faulty. It would pay you to pay attention to this pump for say 10 minutes after a faucet is closed to make sure it doesn't start "short cycling." It shouldn't run again until a faucet is opened or the toilet is flushed. If it does, you have a problem somewhere.
Roof leaks....older coaches are "prime" candidates for roof leaks. Look for discoloration at the ceiling, around the edges and around roof penetrations like the vents and A/C and skylights in the shower (if applicable). If you see discoloration then start asking about whether or not they have fixed any leaks in those areas. If not, then you may have a problem on a rainy day.
As I said in the beginning, ask what type of warranty is offered against failures/defects you discover at a later date. This will give you some time to "test" everything and maybe experience a good hard rain and still be able to get any "found" problems repaired by the selling dealer. If the seller doesn't offer to stand behind the coach for some period of time, I'd get real nervous real quick. The longer the time he offers to "guarantee" the vehicle free from defects, the better I'd feel.
