Unless there’s some big threat coming I would take it Day by day, year by year.

Does this tenant have a history of making veiled threats or constant minor complaints?

First, never mind about the tenant's threat to take you to court because PGW sent you a bill she disagrees with or any of the other issues stated. 

I would threat this as a side hustle and see where it goes. 

A few days later, they were gone...We really didn't want to evict them and had no intention to actually do so, but the threat alone must've been enough to get them moving.

I know it is difficult, but just ignore the name calling, threats and dishonesty etc. 

The only way is a TRO, but the daughter must present a threat to the complex as a whole. i.e. breaking windows, camping in the common area, etc.

I suppose you could suggest to your small bank banker that if they don't give you the bigger line of credit you might have to shop your mortgages somewhere else (but if your existing rates are really good, that's an empty threat!)

But the guy was pretty confrontational and was threating to take me to court.

I imagine their credit rating is decent, so there could be a threat to them their credit will go down.