Sorry one more question that will help others answer your questions... are you planning on travelling around a lot, or parking it for a month or so at a time? Or, am I misreading that you want to buy a 5th wheel and just leave it parked somewhere, with no tow vehicle?
I ask because some places have length restrictions, especially since it sounds like you're on a budget, and may not be able to afford the fancy RV parks that usually can accomodate large rigs. State Parks, COE parks, etc., sometimes have size limitations.
Also, all that said, we've been happy with our Keystone travel trailer toy hauler. No major issues. Others' mileage may vary as there doesn't seem to be a lot of rhyme or reason to quality with RVs until you get up into the very pricey units.