Would be interesting to follow if it's a thoughtful thread...Can you give us the basics of the house - square footage, bedrooms, bathrooms and lot size, as well as what the scope of rehab work would be - i.e. what you plan to spend your estimated $19,000 for?

Split by square footage.

I'll tell you that typically, on a fannie/freddie loan they don't care if the unit or square footage is not permitted, as long as its completed in a workmanlike manner they won't give you a hard time.  

Obviously the 1902 building was not built as a condo.To throw another wrench into the discussion there is another form of ownership called a co-operative or co-op which is used in NYC and FL, where you are buying stock in the company that owns the entire building in proportion to the square footage your unit is in ratio to the total building square footage. 

For example say I found a property and I obtain information on its square footage say 1152sq ft with an estimated value of $125,856, a sale price of $63,000 and the amount in default as being $63,450. how would I determine if this is a good wholesale deal...please help..thanks in advance

I do, however, rent out rooms in my home, and am able to depreciate that sq footage, as well as deduct a portion of the cleaning lady, the gardener, cable, garbage, water, heat, etc. 

But I loved the sq footage and the fact I could get 4 bedrooms and 2.5 baths.House is rented for 1450/mo.2.

You can do it by number of tenants, number of beds, square footage.  

RUBS (ratio utility billing system).Youll have to write this into each lease.To bill unit A:(Unit A sq footage/total sq footage) * total utility bill = amount due from unit A

It could be a bit more, depending on square footage, finishes, etc.