I am looking into buying my first self storage facility.

The account is "Vacasa"'s, not his.Likewise, if Elon Musk decided to buy Vacasa and tomorrow, I'm pretty sure he would retain the accounts as they are assets of the business he's buying, not any particular person.  

I'm in the same boat for reference- I bought into the "buy now, refi later" idea and am sitting on a 7.375% on my latest property acquisition and a commercial line of credit I have is at prime + 1 (so 8.5%).

If the other two parties want to flip a house maybe they can do just that as partners and then sell you the house which you can buy with a primary home loan with low down payment.

We all invest in real estate in order to make money, and keep in mind that someone who can only afford to live in a mobile home and seller-finance to buy the land is probably tight on funds. 

It's a competitive market and most of the people that get in trouble here are ones that buy blindly without actually figuring out the numbers, etc.You'd be surprised the number of times I get asked after month one if their electric bill of $xxx or whatever is normal, and the thought running through my head is "how did you not  check things like that before you committed half a million dollars to something?"

Unless you've done substantial improvements to the building or used a large down payment when buying, it's unlikely this will work.Perhaps your best move is to find a new primary residence that is 2-4 units and repeat the process.

I think asset prices will continue to grow, areas where millennials can buy affordable real estate will be where I'm setting my sights on.  

Simply gifting him half the property now wouldn’t immediately allow him to claim the exclusion without fulfilling this residency requirement, I don't believe.One thought would be to use a HELOC to pull just enough equity out of the current home and use it to buy a smaller home, or at least the down payment.

Reason I ask is there are going to be a lot of real estate ventures where ALL money is lost, and many are due to poor management or buying a deal they should not buy.