Personally, I'd be very conservative in my revenue projections on something like this just in case this trend continues. 

why no MLS  agents may have done a bunch of your homework up front.. just offer what makes sense to you.. me personally I would start with  the zoning maps and only look at props zoned for the size you want to create.. then work backwards.. no sense chasing deals without knowing the zoning up front.

Yes you can use zillow/apartments.com/Craiglist, but the most success i have personally would be FB Market place.

I’m not a greedy person in the least bit.

Challenges?

Another thing to consider is that if it was your personal residence, you may be able to exclude some capital gain income if you sell it within a certain amount of time.Best of luck.

Finding motivated home sellers without a realtor can be challenging, but two effective strategies you can use today are Facebook paid advertising and door-to-door sticky-note delivery.

Even though I was cash challenged I held onto my house (putting past due payments on the backend) and had equity to sell, pay off debts, and get my credit in check.

Even under this scenario, with a 50/50 split, you will not be getting paid for doing all the work.Another option would be for you to put in 50% of the purchase price using an LLC that you own 100%, borrow the remaining 50% from your investor as a 2nd position loan at a fair interest rate with points, and borrow the rehab under your personal guarantee.Better, if you can find a lender who will lend to a newbie, and they are out there, you could borrow the purchase money using some of your cash as a down payment, as well as all the rehab funds using a construction loan.