I looked into this, and the biggest issue is that your Buyer would have neighbors on both sides of them who own the home and the land, which may be a turn off for them. You're looking for a Park tenant in a community full of land owners, which is may be more difficult to find.
You also cannot control the behavior of the adjacent neighbors. If they decide they want to Park 9 cars in the yard and have aggressive breed dogs you cannot address that.
I think it can be done for sure, but the model is odd and may only work in certain markets - I guess if there is enough demand I would give a try and if it didn't work out owner finance the land + home.