Best way to evict a problematic tenant in Oregon?

[Ellie Narie]

They leave oil stains by their garage without cleaning up. 

The other tenants say they leave trash lying around all the time, and that they leave their vehicles parked in a way that gets in the way of the other tenants' driveways. 

They have what appears to be a non-working vehicle parked on the property. 

There have been reports of physical fighting going on in their garage and in their unit, but all the tenants of that unit "consent" to it, according to the records, so there's no "abuse" technically. 

They have a dog in their unit without any deposit or any paperwork that proves it is a service animal. I set a date for them to pay their dog deposit by, and it's about to be due, but they haven't paid it. 

What's the best way to go about all this? I already gave them one warning about all of the above items ("excessive noise", unauthorized pet, parking violations, trash, all in one warning). 

I don't want to run into any legal issues about this, so I'm curious what the best plan would be.