He gets a discount if he buys a lot or seconds or something but he keeps that as part of his profit.

Most banks do not loan for what your intention is, but if you do own the land outright then you do have the opportunity to pursue a construction loan like Ryan mentioned.3. if your goal is to sell plans (approved I assume) then you have quite a bit of expense and months of city approvals/ meetings to go through before that is a reality.

Has anyone ever created a partnership with a vacant home owner where owner retains ownership of the property and the other person (me) acts as a property manager for renting and they split the profits.  

Any way they have suggested a 60/40 split on the profits.

If you still want to pursue the property, then you need to figure out how much it will cost to renovate, plus all of your holding expenses.

What I do is I calculate the estimated profit I would make from a fix and flip.

@Marty Summers If your end game is to fix the house up and sell it for a profit why not just go ahead and do that?

I have several friends/clients and personally even bought a car with crypto profits (though I'm now out). 

The past two years I have done eight deals which were all profitable.

The estate manager and family members are wanting the maximum profit and are willing to wait up to a year or more to sell each house individually.