Wow great feedback, nice to see such an active forum. Many good points:
"I'd be awfully cautious about thinking a particularly small trailer with a wet bath would work for such a long and continuous time. A few days at a time, maybe a week or so, sure - but 3 months trying to live out of a tiny trailer, especially where it rains a lot, is asking an awful lot." Very good point for sure. May be able to get away with no shower and just do that every few days at a truck stop or camp site.
I did come across a "Scamp" in Ontario: Small for sure but cost wise not too bad.
Scamp Trailer