When to use 住在 and when to use just 住?
I am a native Chinese speaker. We say "住这样的房子" or "住在这样的房子里". These two are both correct, and they mean the same thing. 

"住在这样的房子" sounds wrong to me."住这样的房子里" may be correct but sounds weird.

As you may have already known, the time "以前" or "现在" do not affect the form of the verb.

Hope this helps!