We gave a demand for rent & eviction notice about 15 days ago, but they’re already moved out. 

on Friday 5pm), noticed it Friday 5:30pm so couldn't ask my lawyer which was the one who submitted the complaint,yes I have a docket number.

I've noticed vacation rental signs here in Newport Beach where I surf, indicating that short-term rentals are allowed.

Remember that most good tenants give notice at the end of the month, so if you post something for rent on the 25th to get someone in in less than a week, chances are you will appeal to the exact type of tenant you want to avoid.Determine if your place needs any work, leave time to do that and try to post it for rent in the first 10 days of the month.

A possible 4th option came up when I was reading some past BP entries and noticed that some older multifamily properties are grandfathered into being approved.Does anyone have any advice on which route would be best to solve this issue?

This is what I would tell them.If the offending tenant was warned by police or cited by them as verified by a police report then I talk to them about it and follow up with a written lease violation warning aka notice to correct.

I have had to threaten eviction with 3 day notice.

I noticed you do not currently have any REO (real estate owned).

As far as I understand I give them a 7 day notice and they get 30 days to leave after the 7 days.

Went through the process (Notice to vacate, filing, etc).