Here we have 2 adjacent/catty corner lots in Debary super close to Lake Monroe. A house builder owns 2 of the other lots next to these and has offered to build at 105/sf. This will include the cost to clear the lot. That is a pretty solid number, but you would need to speak directly with him to figure out the level of finishes that will be used within that quote. Dirksen lot is 0.259 Acres and Toms Rd is 0.27 Acres.
As far as comps, you have a new build that is 1,570 sf and sold for 237k and an active that is 1,670 sf that is listed on the market at 267k. The active is still in pre-construction too.
At 1,650 sf, your cost to build would be about 174k per house. You would be purchasing each lot for 25k each. So, you would be all in for 200k plus closing costs. If you can sell for 260k, then you are looking at a return of 60k or so minus closing costs/holding costs.