After looking into it more, I'm concerned about potential tax implications and legal issues, such as piercing the corporate veil.

I also manage hundreds of residential and commercial properties outside of STRs so I actually understand how seller friendly these platforms are compared to the legal and government system outside of STR world need to deal with.

@Rud SevHere is a start:https://www.biggerpockets.com/forums/51/topics/839015-are-sy...https://www.biggerpockets.com/forums/51-tax-legal-issues-con...

We thought about hiring a lawyer but the legal fees were expected to be in the range of $10k to $15k and would have taken months (if not years).

They are always updating the ADU guidelines and thats a bit of a unique situation. 

Are you aware of city of San Diego rules regarding converting existing legal space to ADUs?  

Can you buy a house with a legal suite?  

If you need financial help, ask under the "Finance, Tax, and Legal" forum.

I was interested in the finance and legal aspects of operating a multi-state buy and flip equity fund.

It will also require extensive networking to raise funds from other, legally, to buy at scale.Recommend your plan be more realistic with a goal of 10 years for your real estate to be generating enough cash to live off - and even that may be a bit optimistic.How to grow?