Nice concept and execution, the little houses and mushroom people are cool and funny :)
As others have said, the progression is too slow to get players easily invested in the game (especially in the context of a game jam where you have a limited time to allow to each game you try)
And it was very frustrating to buy a building that you cannot use, having to pay basically double to even have one single guy with that new ability...
Other than that, I liked it a lot! With those two things fixed I could have spent a lot of time playing, trying to please the Mushroom Lord ;)
Good job!