When we bought our Grand Design 385TH, we were living in an apartment. We financed through our credit union. Check your credit score, know what it is. Generally, they say 760 is good enough to get approved, but the higher you are over that, the lower your interest rate will be (especially when you are over 800, the benefit seems to top out at 81x or so with most banks). On ours, I got a rate lower than what the CU advertised. The same thing happened when I bought my truck, and I'll have it paid off long before the loan term expires.
After two months, we decided we'd rather live in the trailer. I have a full-time job, so we can move around from park to park in the area - most of them offer good monthly rates. Some of them include the electric, some charge extra for it.
Get a mailbox at a centrally-located UPS store and set that up as your address. That way your mail stays constant even when you move. We found one that's good for the CU, insurance, everything sees it as a residence.
If you have the money, go for it.
Our CU never asked about full-timing.
Our insurance was interesting. I bought our truck first, and kept getting question forms from the insurance company about "Do you use it for work?", "How many miles a week is it driven for work", phrased about 5 ways to see if they could get me to say I used it for work (which I didn't and don't). I bought it planning to get a trailer. Once I bought the trailer, the question forms stopped coming. I guess at that point they could see a reason for it.
