We took legal action and got a legal judgement against him. 

I would imagine the best actions would be to immediately fire the management company, pass the keys onto a new one, sue the old one in small claims court for the listed damages.

Should I continue mediation or pursue legal action (considering the time and costs involved)?

If the seller misrepresented tenant conditions, consult a real estate attorney about potential legal action.

San Diego’s average house hold income is about what you stated, but the median is a surprisingly low (considering US news and world report lists it as the most expensive US city) ~$100k.  

They're such a massive campaign that it seems unlikely, but with too much guest-first action you can expect a small shifting of the tides.

https://ktla.com/news/nationworld/airbnb-nightmare-tenant-leaves-los-angeles-home-after-nearly-600-days/#:~:text=(KTLA)%20%E2%80%93%20Elizabeth%20Hirschhorn%2C,according%20to%20a%20court%20filing.

Yeah @Kent Fang ching, you detailed a couple of the strategy actions we are doing for clients right now in MN. 

They had 270+ days to take action, but they didn't.

They're scaring me... a lot.Of course, we're only hearing about the worst cases in the news.