Are there any creative but legal ways to use my personal funds and the SDIRA on the same projects?

If I were you, I would contact an estate lawyer, or have the siblings contact one, to legally see what the other 4 siblings options are.

I know its not legal.. but I self insure myself in that regard. some say its recession proof and some say not.. my banker says not.. he says when economy gets tough they just won't spend 200 bucks a month to store their stuff they either up and leave it or move it somewhere else.. so that's two opinions.my units were quite unique one they were A class and two right across the street from 300 floating homes and all my tenants save a very few had house boats.. so I kind of had a captive audicance and once I got it converted to mainly all houses boats..

But at least you can know what you are getting into.As @Brian Adzadi pointed out, you want to make sure it is up to code, any renovations were properly permitted and professionally done, and that there are no violations that can surprise you down the road.

@Matt SearsGo to the tax & legal forum - you can meet a number of experts there, as well as ask your questions.

What legal steps do I have to take to form a partnership in terms of financing.

Alexander, Yes a great RE lawyer is over PDX legal solutions, tell Henry Rau that I sent you his way.

Anybody have a lawyer approved, legal verbage, legit whole sale contract theyd be willing to share? 

Legalities?

I pulled a permit to build a single family home, lined up the financing, etc.