I bought an old 1983 Jamboree and it has been a crash course in RV restoration. I had to completely rebuild the cabover and have done a TON of work all over. If you are paying less than $20K for a motorhome, you are looking at high mileage or older MH's and have to really know what you are looking at. Otherwise you can end up with something that might need major work.
It sounds like you want to buy an RV that DOES NOT need work. Also, in California it seems like you can't get a loan for anything over 10 years old. With the above in mind, you will probably be shopping for RV's ranging from $25K and up.
Short answer is that if you want something used that you could feel comfortable jumping right into and using today, then you will want to buy in the $25-$35K range from a rental fleet or dealership.
Now, forget about price. I believe THE most important place to start is floorplans. I REALLY like my 26ft with no slides. Slides will leak and are another thing to maintain. The extra floor space really is nice, but I just don't think the tradeoff is worth it. They do make 26' RV's with rear Queen bed, but ours has a full in the back corner. That works for me (6', 260lb) and my wife. It takes a night to adjust, but with a memory foam topper, that bed is REALLY comfy. I also highly recommend you NOT get the dinette floor plan. Ours has jack-knife couch and removable table (on two posts) instead of a dinette. So you can have the table up to eat and then have clear floor when you are done. Our floor plan also has two captain chairs across from the couch with their own pop-up table. The couch folds out to a full size bed and the cabover is a queen.
Ours has been an adventure in repair work, but we LOVE going on trips as a family. My daughter absolutely LOVES her cabover "kingdom" and DW and I are excited and happy when we go on a trip. Best of luck finding the right rig for your family.
Jose
