My personal experience with used RV's runs about 40 years so I thought I would share some things I look for.  If you are buying a used RV without looking at it first, be prepared for less than you thought you were getting.  Why?  Pictures just don't tell the story.  The seller will remember fondly the camping trips with the family but will not normally list every repair done.  Most honest people will let you know on major repairs and they will certainly tell you about updates or new equipment in the RV.  Well enough of that.  Just remember these things....An RV that comes from a harsh environment will normally have more wear and tear.  I have seen RV's kept in Northern states with mice and frozen pipe damage.  On the other hand, I have seen RV's kept in the Southern states in great condition.  In a warm or hot environment though, I have seen faded decals and bubbled laminated siding.  Go to the bookstore and get or have them order you a book on how to buy a used RV.  It may save you thousands of $$$$$.  These books are very good and some show you pictures of exactly where to look and what to look for.   One guy didn't like the leaks he kept getting in his water lines and replaced them with stainless steel flexhoses.  If you are going to keep your RV for quite some time and you are a bit of a handyman then go ahead and upgrade the water lines.  My experience with water lines is most manufacturers use cheap!  Yes you still have to put the anti-freeze in them in the winter if you live in the north.  More expensive RV's have a compressed air closed system that once you drain all the water, you use compressed air to flush out remaining water.  Broken water pipes cause alot of damage, sometimes hidden.  Open the cabinets and cubbyholes and look for water marks on the walls or floor.  If water lines look like they have been repaired with new pieces or connectors, push or step on the floor to see if the flooring is soft.  You might be buying an RV with water damage to the floor.  Look at the printing on the PVC pipe and if the brand or markings are different or coloring is slightly off, then there have been repairs.

Next, ask when the last time the wheel bearings were greased or replaced.  Some people will NEVER do it because they don't KNOW to do it.  Whenever I see a camper or trailer broke down off the interstate, that flat tire is usually the result of higher road speed building up heat in the bearing, bearing failure and then the tire dragging.   The tire blows because of the heat buildup. Then you have to go to the nearest town and hope they have the correct bearing to fix your camper.

Don't forget to look for the obvious.  One dealer fixed a leaky roof and then had the inside professionally painted.  The job looked too good!  I asked him how long had it been since the roof leaked and he said they didn't know much about the campers, they just sold them.  That right there should be a very BIG WARNING SIGN for you to run out of there fast.  If you look at the ceiling and it appears that there are additional screws that don't fit the pattern, there is a pretty good chance that the ceiling was sagging.  BEWARE.

Crawl under the RV and look at the complete substructure.  Are there any patches in the flooring?  Does the frame look straight and true?  Are there any extra welds to the frame?  This may be related to an accident.  Look at the tanks, gray, black, and clear.  Look all around the tanks and pipes and connectors for any leaks.  Number one cause of a cracked or broken tank is backing over an unseen obstacle just ask me HA HA.

Tires and appliances are pretty easy to judge.  I knew one guy who bought 10 ply special ambulance tires by Armstrong.  They were so good, they had curb wall wear indicators.  They were tubeless but he still put top quality goodyear tubes in them.  He never had a flat.  That may be extreme for most other people but he drove to Canada and Alaska alot over gravel.  To each his own!  Look at the sidewalls of the tires.  Weather checking, or cracking of the sidewall, is usually the result of not removing or covering the tires during storage outside.  The tread looks good but there are cracks in the sidewall.  You can get innertubes to help but if the cracks widen significantly when you air up the tube, then err on the side of safety and replace the tires.  Some dealers will coat the sidewalls with tire black to cover up the cracks because they don't want to pay for new tires.  If any cracking is present, demand replacements or a discount on the price.  If the appliances look in good shape and the interior looks in good shape too, then the previous owner probably took good care of the RV or didn't use it much.

If the carpet and upholstry look bad or have stains or burn marks from cigarettes, you might want to pass on the RV and keep looking.  If you can get it for a great deal, then ask yourself if you want to sink the extra money in getting it up to your standards.  An honest dealer will always get you a ladder to climb up and look at the top.  Look for patches, look especially at the four corners of the RV.   Is there any excess sealer there?  Could be the sign of a leak.  Pay particular attention to the entry point of the antenna and vents and air conditioning.  Look for a good seal there.  Old or cracked caulking or sealer should be replaced now.  Beware of luggage or storage racks on the roof.  If these have been used alot or overloaded, they will cause a roof leak. 

Finally, I will leave you with this....If you buy an RV sight unseen, be prepared for some surprises.  If you must do this, then have the RV inspected and pay the inspection fee.  Don't use an Inspector recommended by the owner!  You can find them in the yellow pages.  Have the report fax'ed to you before bidding ends so you can negotiate repairs or discounts with the seller.  Inspectors should be licensed or bonded or both in the state they work in.  Don't hire the first one you talk to.  Get estimates from 3 inspectors.  Always tell your inspector that you demand their secrecy.  Tell them it is unethical for them to discuss anything about the inspection results to the seller.  Tell them you are paying for the inspection, not the seller!   I am fortunate to live in Indiana where I can go to the RV parts wholesaler in Elkhart and get a replacement part if I need it.  You may not be so lucky.  There is an old saying that you get what you pay for.  If you're not good with repairs and live way out in the country, then consider buying a newer RV and a well known quality brand.  If you are not sure which brand is a higher quality, there are a number of used RV price guides that you can reference to tell the difference.  Just match the same year RV with the same size and options and look at the price difference.  You have less of a chance for something breaking or part failure if you purchase a better quality RV and a better chance that the part can be found to repair the RV.  NEVER NEVER NEVER BUY A USED OR NEW RV ON YOUR FIRST VISIT TO A DEALER.  SHOP AROUND!  IT'S YOUR MONEY.  Let someone else buy it new and suffer the depreciation.  They get to work out any bugs in the system.  You get to buy it from them for much less.  Try to find out why they are selling the RV.  If you are buying from a dealer, ask for the name and phone number of the previous owner so you can ask them any questions.  If the dealer will not tell you, LEAVE.  A reputable dealer will tell you the name and number or call them to see if it is OK for him to give you their number. 

I almost forgot the electrical!  Look at the fuse box and wiring.  Melted or discolored wiring or alot of splicing should tell you to beware again.  There may have been or still be a short on the electrical system.  Ask what repairs were made and what happened.  Ask for all extras that go with the RV.  Ask if the Tow Dolly goes with the RV. Ask if the equalizer hitch goes with it.  Negotiate a reduced purchase price if they want to keep extras. Ask why.   Hope this helps.     

I am going to update this today 03/09/2008 to give you some more ammunition when buying from a dealer.  Everyone knows that there are two kinds of dealers, one will let you walk around their lot on your own and watch which RV you go to first.  Then they will come out to help you and try to sell you the first RV you looked at.  Why?  Statistics show and dealers teach their salesmen (women) there is a higher probability of you buying the first RV you looked at than any other one!  The other kind of dealer is the Mega-dealer.  He brags on TV he is the largest RV dealer in the country and he has the best deals.  He DOES NOT!  They have a well stocked parts department and a large selection of camping accessories.  They also have free hotdogs and soda pop and popcorn for you.  And they will drive you around the lot in a golf cart.  (ALL OVERHEAD YOU WILL PAY FOR) The salesman will show you what he has been told to push but not necessarily what you want.  If you offer a lower amount, be prepared for the used car salesman bit.  You know the salesman says he has to go talk to his General Manager.  Bring a book or magazine to read because they will use the old "stall" tactic on you.  Another tactic they use is to lay a guilt trip on you by saying you are wasting their time while they could be selling an RV to someone else to win that trip to Hawaii! They will pull this one on you at the far end of the lot and you might be walking back to get away from the salesman.  Most dealers will want to finance your RV because their cut from the bank is very good. 

One RV that I bought was financed at my personal credit union for 3 per cent lower than the dealer offered.  The dealer offered to handle financing and had a dozen banks and credit unions he could go thru.  My credit union was on his list and he was more than happy to write up the contract at 9.5%.  I questioned this because my credit union had just mailed me their rates in the newsletter that comes with my statement.  I still bought the RV but carried the purchase contract directly to the credit union.  Later, I spoke with the loan officer at the credit union who said the dealer typically gets a lucrative "finders fee" for using their credit union and this is normal throughout the industry.  So talk to your lender before you buy.  Many have pre-purchase loan qualifying options.  It is a free service.      Happy Camping!