I have been working on this one for awhile and I have 2 versions: the more difficult 4x4 version and the slightly easier 5x5 version, the 5x5 version is better suited if you have only the base game or...
Well the new 10x10 building up challenge is impossible, you can only have a total of 4 stories. Oh well....I still like the idea of cramming sims into a very small house. *evil cackle*