You hoisted a giant "I have no idea what I am talking about/doing" banner right there. 

laws are the same in Oregon and Washington as well.. just FYI.. its why i got out of the foreclosure rescue rent back way back when the laws were enacted in 08.  

Also worth considering who is your labor force, is there a required assembler, is there a certification your GC needs to have this be Warrantied, consider the cost of rigging/hoisting, scaffolding, etc.

The other issue you have here, is you are trying to build tall, which means that there is a natural increase in cost simply for getting everything up to the upper floors because it is going to have to be hoisted up there with a telehandler or a crane.

And as we know foreclosure rescue ( which was our bizzness along with courthouse steps purchasing) the sub too foreclosure rescue rent back became illegal in Oregon and WA and highly restricted in CA. 

There's been cases when someone bought  dozens of properties subject to, fell behind on all of them because of tenant problems on some of the properties, resulting in dozens of motivated sellers, thinking they solved the problem dumping the problem on a rescuer, losing their homes, and having bad credit to boot.There were extensive discussions on real estate boards regarding the issue: Subject_to_problemsIf you're taking about a 2 year master lease, maybe you're thinking of leasing with option to buy.

Whether the "rescuer" lies about what will happen when the foreclosure takes place, or takes title with a promise to rent-back at an unaffordable rental rate (only to evict the prior owner later), or whatever, the end result is someone other than the homeowner ends up with the equity.

If you get too fancy you run the risk of hoisting yourself on your own petard or making it look like you are trying to hide something.The key is that the advance is a fixed dollar amount.

As opposed to framing where you a need a team of people to hoist large sections. 

Landlord as rescuer never works out well.