@Mike ReynoldsRegarding your comment that if you need funds you can use money from your side business:You can't use non-retirement funds to pay for expenses related to real estate held inside you Solo 401k.Subject to the contribution rules and income limitations, you may be able to contribute non-retirement funds to your Solo 401k (e.g. as an employee or employer contribution) and then you could use the funds in your 401k to pay for expenses related to real estate owned by your Solo 401k.

Would I be able to rent out both my main house and ADU and not be subject to the owner occupancy rule?

The sponsor if they even consider allowing you would be a huge red flag for me knowing if they will accept non accredited investors what other rules are they breaking. 3.

No, ok, rule in your favor.

The most important rule is to have the cash flow of the new property be able to pay all its expenses, mortgage, AND the line of credit back.

Dodging Toy Shop RulesIf you run a shop (have a license), you’ve got rules.

Are there rules about renting it out?

I see what you're saying about the 2% rule. 

Still tons of positive cash flowing deals that meet the 1% rule and amazing appreciation here!

It requires using a home automation platform (I use hubitat), creating an API, and creating some rules within the automation platform.