I have about 100k in assets both personal and business I could sell, but part of me thinks that’s extreme and I’ll sell “myself” along the way with all my stuff.  

I personally don't mind cooking on electric but I will say that cooking on propane is different than what most people know which is natural gas.

It's not a personal sale between you and your son, but rather a sale from one LLC to another.

We recently relocated to Phoenix last summer and I'm starting to look for recommendations for local credit unions here in Phoenix which are trustworthy, low rates, personal touch, easy/simple to work with, etc. 

Primarily for personal use for the family as well as an investment (but the numbers need to work), I am just starting out searching for a property so I am open to all suggestions and comments.

I bout one in 2019 and it has turned into a gem for me, but at the time, it would not have been 1.25 1.25x is a very common DSCR for a bank.

I would start close to where you live personally. 

Keep in mind, you can’t use personal funds or your home's equity to directly fund the SDIRA investment, and all property expenses must be paid from the IRA.

Quote from @Brandon Croucier: 12 or 24 Month Bank Statement is probably the best bet.Where would I get one of those? 

I personally feel it's very intrusive to call someone like this, but maybe it's considered acceptable?