You might want to consider asking around one of the Sims Mod Communities.  They would have an idea if anyone did.  They might at least be able to get something into an obj file for you.

If not you might have to get wings3d or blender or something and remake your houses manually.

WARK!

Thus Spoketh Winterclaw: a blog about a Winterclaw who speaks from time to time.

 

(using Poser Pro 2014 SR3, on 64 bit Win 7, poser units are inches.)