Quick - Need Deets to Buy this House!

[Matt Vaughn]

Quick question so I can put an offer on this house (property #2)!  There's this great opportunity for a split foyer house that's in good shape and has only been half-finished.  From the split foyer, there's a door at the bottom of the stairs going down, and on the other side of the door is unfinished basement.  Currently it's a 2 bed 1 bath house.  Built out downstairs (as I have seen identical houses in this neighborhood do), this can be a 4 bed 2 bath house.  
 

Here's the $100,000 question:  Right now, most of of these houses are listed as 850 SF houses with 600 SF basements.  If I try to flip this, what can I do to make sure this gets listed as a 4 bed 2 bath and not a 2 bed 1 bath with finished basement?  Can I put down an offer now contingent on me discovering whether or not this is possible?

This property is in Jessup Maryland in Howard County near Columbia, MD.

Here's a photo of the condition: