At the risk of sounding glib, the Detroit Land Bank has some amazing deals on adjacent vacant properties when you buy a property to rehabilitate. If a family wants to have their own virtual compound and can stomach the safety implications, buying a Land Bank house and adjacent properties would give everyone plenty of elbow room.
In my city, you can often find rows of houses for sale for $5-10k a piece from slum lords trying to exit the business. Tearing down the old homes would probably be expensive, but I think the city even has a program to help with some of that. Since you could effectively buy a whole street, the safety implications might not be as bad as initially assumed.
