He'll soon find out that indecent exposure laws can apply to the inside of your home. 

Using  your personal SSN for a legal entity is a mistake - -you tie the LLC to you creating the legal exposure that the LLC was intended to create.

If you are doing the right flips, it can be.An alternative option within the tax-sheltered IRA/401k realm is not to have the IRA be the flipper and have exposure to UBIT, but rather to lend hard-money to other flippers.  

I do not have millions yet and $150k is a lot of cash so want to understand my exposure which seems great.

Websites are a fantastic way to gain exposure.

When you keep repeating this you will end up with a lot of properties that cash flow less than your first one but the aggregate will much bigger (plus you will be diversified, have more exposure to appreciation and move depreciation tax benefits)

I agreed with what you said,  but disagree with the emphasis  because if there is potential exposure to a discrimination claim (absolutely agree) then whether or not it is of itself a protected status is of less importance.

Zillow get's the most exposure. 

If they are lending money to you to buy the building on 123 Main Street, they only want exposure to risks from 123 Main Street, and not from a bunch of other properties that you own elsewhere.

IMO,  STRs are a poor business model in the first place due to the high turnover and exposure to excessive vacancies.