Yeah I say pre-retirement since in my current job and a range of similar jobs for this company, or similar companies, I could do it from anywhere.
But of course that's not really true for my wife, she has to build up a base for her clientele and changing geography all the time isn't really conducive to that.
As far as the practicality of a boat or RV, it's not. There's no way to justify owning either, if you're thinking about ROI or net usage. On a bad year, we'll only use the RV for about 2-3 weeks total, which includes maybe one solid week, and a bunch of weekends. On a good year, it's more like 3-5 weeks. Even still, the RV is sitting idle for 90% of the year.
HOWEVER, when I'd decided to get rid of the Airstream and was balking at the cost of buying new, more modern replacement, my mom of all people-- who is decidedly frugal-- told me this: "Your kids are not going to be small forever, you're running out of time to spend with them, and if they love it and you love it, then this is one of the best ways you're going to have, to make some lasting memories with them." And she was completely right. The only ROI you have on something like that, is making memories.
So I get the RV out as much as our schedules allow, and we have a great time, and then it sits idle most of the year, and that's okay with me. Because the memories are worth it.