It began as a persona residence then became a long term rental and then it became clear that in this area short term vacation rental are very profitable and if you stay within the confines of the regulations I think they can be fairly safe long term.

Figure out if they are coming to you because other HMLs are saying no.Make sure that whatever contract includes an option for you to take ownership of the property for the value of money loaned + whatever the person put down.Make sure the property is worth (at wholesale prices) what is being suggested.Or,  just offer instead to pay the person a finder's fee and buy the place yourself if so inclined.Or,  find other HML's and offer to work with them for a while to learn the ropes and ignore this guy.Caution in any case.

Of course, this means that Airbnb ends up calling me asking me to give the person a 100% refund which I refuse to do.

That will vary greatly from person to person.  A

If you're rolling out of your SF portfolio, you could still use the first agent for those sales, and you can also refer other SF investors to that person. As

If Person A does great and is flush with cash from how great this was, then it's Person B's turn to buy a home, and Person A has the capital to be the private hard money lender.

I have a long ways to go but my goal is to talk to at least one new person a day and let them know what I am doing.  

Ask yourself - Would you do business with this person? A

@Daniel TrostMy understanding is that you can only get the 121 exclusion if you sell your property to another person. A

But of course that depends on your own persona financial situation.