Homeless housing-I could do that
I've been kind of losing the dream lately. But I definitely could do this. This group makes micro houses for the homeless. It costs less than $1000, probably a lot less if you scrounged up materials (It's amazing what they throw away at construction sites.) These guys even tell you how to make a stove out of metal buckets. The pictures are not very instructive, but they have lists of materials that they use.