Duplex - Rehab - splitting a deed & do these #'s work?

I have my eye on a duplex property that is listed for $135,000. It has appx. 1 acre and each side is 1500 square feet. 1 unit has 3/2 - the second has 4/2.

So my thought was to purchase this property and upgrade each side with the intent to seperate the deeds to sell as a “duplex”. Does anyone know anything about the legal aspects of selling a duplex?

Also I wanted to market this property to low income individuals (there is a shortage in my area). If I list each side at $120,000 then I think we could easily sell the property (it is in a very rural - blue collar town). Also, I was thinking that we could offer to carry the mortgage or offer a lease option. The negatives to the property - is that it is on a main road…but the lot is a good size and the house has good bones.

These are conserative numbers - do you think they make sense?

$135,000 Purchase price of rehab
$30,000 cost of repairs
$0 assignment fee
$5,822 7% of loan/12 x 6 # of mos held
$0 0% Point(s) for loan origination fee
$1,350 Other purchase fees
$2,200 Holding cost= # mos x (taxes, insurance, utilities, etc.)
$1,350 Hedge factor
$11,000 Sale fees
$186,722 Total cost of project

$220,000 ARV (After Repair Value) Low end
$20,250 15% goal
$33,278 Estimated Profit

Any thoughts on this one?