Yea, legality might be complicated and not worth the trouble.
Just looking at 3-6 months stay in each place.
I'm not sure if you are saying that you are prepared to just do this illegally, or if you would change your plans if Visas are an issue. If it's the former, please don't be the asshole who goes abroad and takes jobs from the locals illegally.
There is a very recent thread on MMM about work-for-board programs abroad like WWOOF that allow you to work on local farms on order for free room and board, usually.