Lots of questions here.
Yes, it does make a difference if this is a weekend/vacation camper or your full-time residence. There are several insurance companies/agencies that specialize in coverage for full-timers. None of them are 100% great or 100% awful. Talk to several and make your own decision.
One question that you will need to ask about is value of your coach. A standard policy basically says that they will pay you book value if they declare your coach totaled. They will take that book value from NADA or similar company. Look up your coach on NADA and you will see that it isn't worth much. How much it cost you doesn't matter at all.
For an increased premium, you can get a policy that will pay you what the coach is actually worth. You will need to present an official appraisal periodically, and that appraised value will be what is used to set your premiums. I'd suggest that you discuss this point with each agency/company you interview.
If a thief wants your coach badly enough, there isn't much you can do to stop him. I recently watch a video of someone backing up to a trailer that had a locking device on the hitch. The "thief" (this was a demo, not a real crime) simply backed up to the target trailer, hooked chains around the tongue and attached them to a hook on the truck. He even hooked up the lights. Total time was about a minute.
Best deterrent is to park where everyone can see the trailer (well lighted, public, guarded, etc.). If the trailer is to be left for a long time some people take off the wheels, leaving it up on jack stands. There are several threads here about this subject, so read those and draw your own conclusions.
It sounds like you are going to do a major restoration. I'd suggest that you have a building that you can lock. Put a fenced dog run on it with a "doggy door" for a large dog with a loud bark. That won't stop all thieves but it may deter a few. Best breed is one that is large, slobbers, and sheds.
David Lininger, kb0zke
Heartland mpg 181 (sold)
1993 Foretravel U300 (for sale)