I've done this for years with Island Living but as HollownessDevour mentioned, the Natural Living skill adds another dimension to it since it's been added. I make my Sims survive with nothing on a deserted island and eventually they not only survive but they prosper sufficiently to build themselves a house elsewhere.
I've mentioned this before when players have talked about this theme, but the last Sim that I played as a castaway was also a crafter, Freegan and forager and while surviving on an island she made her own home. Everything was foraged or hand made. The only thing I had to buy was kitchen units because she was dumpster diving with Eco Lifestyle and couldn't find matching units. I made her house out of wood and glass walls so she didn't even have to buy windows. I set up a public workshop so she could eventually travel there to paint, knit, make flower arrangements and pottery, etc. But what I liked about Castaway was that the Sim had to actually collect the materials to build the house structure and I'd like to see that in the game again.