The only down side to being older, in my opinion (other than physical limitations mentioned) is not wanting to gamble on having to start over by making mistakes due to ignorance of laws or a market or being taken advantage of by a bad PM. 

To not accept them is just a gamble on whether or not you think your applicants are not savvy enough to know they can sue you, and that is a gamble I would rather not take in a place like San Francisco.

Some random guy walking down the street throws a cigarette on your lawn and ignites it and that causes your neighbor's house to burn down. 

As both a short and long term rental owner I’ll just add a few words of caution here...AirBnB and other vacation rental sites like HomeAway are great for the purpose they originated: short term rentals, but they offer minimal protection for the concerns of many owners needing to secure their properties for longer lease terms.As a traditional property manager I’m far more interested in ensuring I pull a full criminal background check, speak with a potential tenant’s present and prior landlord, confirm consistent employment/income sources for > 6 months, and ensure a potential tenant has a track record of paying other bills they have agreed to in writing like credit cards, car loans, and others.On the contrary, at best AirBnB/HomeAway/others give me the following info on guest/tenant: a blurry selfie (that could be their dog)confirmation of a non-specific government IDconfirmation of an email address I can’t seecurrent city/state of residencelist of reviews by individuals running a different AirBnB (that I have no way of confirming is not the guest’s best friend)Property insurance secured by (and in the interest of) someone who is not meWhile I’m OK with taking a gamble on unknown guests using my property for short term stays, stays of longer than 1 month generally involve: Someone looking to move significant belongings in with them (that I cannot legally remove in most states)Moving in for a period of time they’re generally unable to pay for entirely upfrontTenants receiving access only after a legally-executed lease, criminal, background, credit, and income check that’s par for the course in a professional, term stay arrangementEven beyond the blatant lack of risk mitigation tactics common in long term lease agreements, the fact remains that many STR platforms are also skimming 10-20% of gross revenue off the top of owners’ profits for little beyond the initial SEO and payment processing.

I guess the main reasons I’d want to keep the house are 1) ego - to be able to say “I own a rental property” and 2) hope for things to magically turn around and one day sell for profit (gambling...)What would you do in my shoes?

To me, one is an act of kindness, the other would be funding what equates to a gambling addiction.I'm glad I'm not in your shoes. 

He became a devout born-again, ditched all his gambling buddies and started spending all his time in church.

I see it as a form of gambling. 

However, that's a gamble and not a good business model afaiac.

A 720 probably would have got me a slightly better rate, but I didn't want to wait and gamble with the market if rates went back up higher.