I would actually recommend the 6000xp for a 5th wheel set up. It's a little more compact, you still get 240v. You can parallel them to get the 12kw that the 18kpv would normally have as well. The 18kpv also would work well too.
Regardless, they all work with or without grid power, and have remote monitoring. You can get a 4g wireless adapter that will let you monitor the inverters without wifi. This is specific for the 6000xp and 18kpv though.
I don't want to violate any of the rules or terms and conditions of the forum, so I will stop here. I don't want to look like I'm trying to sell you on them, just explain the applications they can be used in.