the worse built motorhome you can think of

I think you have to look at the MH manufactures reputation and how long they have been in business, that should tell you something of the quality of their product. If a company lacks owner satisfaction they won't be in business long or will go bankrupt. Another thing to look at is, is the MH an entry level or a high end. The fixtures in an entry level rig are not going to be as nice as an high end rig. We looked at a 2011 MH that was new and from a good company, however, the light fixtures in the rig were really cheap like the dome lights on a car and the plumbing fixtures were cheap as well. If you are looking used look for a higher end coach made by a good company that has been well taken care of with good maintenance records. All MH companies/models have their followers who will defend their rigs and get insulted easily, no one wants to be told their MH is substandard which is understandable. If you go to forums with specific MH models like irv2 you can check and see what models have the most complains and make you decision that way. Lots to consider and another good way is just visit lots of RV dealers and poke thru lots of MHs and really take a look at how they are built. Does the MH have solid doors/draws or are they hollow or plywood covered with something, are the fixtures nice or cheap, are the sinks plastic or stainless steel, etc. You can tell cheap from good and check all the nooks, etc especially behind cabinets, etc. Good Luck and Happy Hunting!