I have been looking at my year end numbers and most of my properties (STR's of course), will have generated over 3k a month in net cash flow on a 12 month average.

I've been using Avail to generate leases and collect payments from guests for my MTR but I don't think it has comprehensive enough features. 

The strategy involves using the HELOC for a flip to generate fast cash, reinvesting profits into long-term rentals, or exploring alternative ventures like short-term rentals or partnerships.

The problem is the HOA doesn't allow VRBO rentals, only year long leases so I wasn't able to generate cash with this property.

The LLC will not have any employees and won’t conduct business or generate income in CA.

@Eugene Lubman Selling the property to your parents allows them to generate passive income while enabling you to perform a 1031 exchange to defer capital gains taxes.

You may also be able to turn the property into a syndication and generate extra cash by listing it on a platform like lofty.ai

No auto-generated financial reporting, but owners can generate their own reports through their portals.

While an SDIRA will have UBIT on leveraged real estate, a solo 401k is exempt from UDFI (unrelated debt finance income) generated UBIT.

If their credit history is sufficiently long to generate a reasonable score for them then the credit score tells you the answer!