There are small single family houses for sale in Milwaukee under $100,000. I’ve brought this up on the Milwaukee Reddit and the people on there seem to believe the only worthwhile places to live are in Wauwatosa, Bay View, Shorewood, etc. But not in Milwaukee.
To expand on the mechanics a bit: The land is rented to the homeowner for the duration at like $5 a month, and upon sale (at a fixed price) the equity is split equally with the trust.