Unfortunately, motorhoming is becoming a DIY hobby. You need a doctorate in fixology.
I had some warranty stuff way early on but it's been pretty good over the years. Still, if you can't fix stuff you ave to rely on a very flakey industry with spotty coverage and minimal training. Some shops are really good, some are, well, just not.
Keep trying. Oh, and for OP, yep, if you like it buy it and wait for them to fix all the stuff before you take delivery. Make a deal with them, make them work for it. LOL