I have been trying to find if there is a wall assembly material that can act as stuctural, shear strength, insulative, interior surface and exterior surface.

Where each party has some skin in the game holds everyone accountable.

Once you rehab it and maybe put $50k of "sweat equity into it", it would be worth $200k, but they would sell it to you for $150k seller financing after the down payment.So, on the surface it sounds great because you aren't coming out of pocket, but in reality if you have the means to close the deal in cash or with any kind of financing like a hard money loan you would likely be better off. 

That being said, there are a lot of ways to skin a cat.  

.- Have some skin in the game.

I stick to sponsors who have at least one full real estate cycle of experience with little to no money loss...ever, conservative leverage, high skin in the game, reasonable compensation ( so they aren't incentivized to push the risk envelope) etc. 

Quote from @Robin Simon: Quote from @Erik Estrada: Don has a harsh way of putting it, but on the surface, I completely agree. 

I had surfaces that just wouldn't hold paint.

A year of rent sounds great on the surface but I'm wondering why they wouldn't just pursue a normal year long (long term) rental...maybe they've been bad renters or have bad credit or low income.

Inventory is low and activity is high, so 3.5 percent down isn't going to entice a lot of people to jump (low skin in the game) unless you are paying substantially more than someone with 20 percent down.Also, FHA and off-market almost never go together.