USDA is very close to fannie mae/fha with property variations, much eaiser than fha.

Good luck out there.Actually, I was seeking a list of strategies and their variations that will allow me to do deals via the 2 components of the HML funding deals at 65% an any sellers that I come across that are willing to wheel & deal w/a 35% carryback for what I for see as "lump sum now - cash over time - and a lump sum later."

Maybe different variations but remember, you can have some if the pie or none of it.Just encouragements here, I'm not being critical of your choices...

One variation you could consider (though I’ve not heard of it done in REI before; speaks more to my relative newness to the field than anything else) is convertible debt.

Are these units all the same or is there variation in size and features?

Repeating that with minor variations is simple compared to finding an existing home and renovating that with the same consistency in many markets.Cons to this plan:Contractors and builders are NOT the same. 

There's a huge variation of services for such homes.

Note that in listsource you'll find two variations and the details are further complicated based on which one you select:For the "Original Loan To Value" criteria, it is just as you suggest - simple math, at least for purchase money loans. 

"Sandwich lease option" or some variation.

If funds are not available the borrower may need to go stated or no doc.The variation of these is why long term goals need to be addressed.