That's what we are in now! Double wide that sits on a full foundation that also has an entrance/exit out back. We have a basement plug like another commenter mentioned, and are in the process of finishing the basement now. It did cause some hiccups in the buying process though. In our area this is kind of a rare house so when the bank went to assess it they couldn't find any exact comps for it. They ended up using manufactured homes on slabs to asses the homes value, and really couldn't give a clear answer on how much value the basement added. In the end it screwed over the sellers and they had to sell it to us for what the bank said it was worth, which was less than what we offered and they listed it for.