Ok, I have already a call in with Legal Shield on this, so, I'm fully aware that what you're answering is not legal advice. 

I have a situation, in Georgia,  where 1 of 3 roommates in a unit (part of my 10 unit artist community) is a huge problem - not only to other tenants in other units, but also to his 2 roommates. 

He's beaten a tenant in another unit, who didn't want to call police, but asked to please let him move out, as he feared for his safety. I let him go, as he found other tenants to replace him. He brings in sketchy friends that hang out on the property and who intimidate other tenants (which is really a community, but now people are staying in their own units), as well as the other 2 roommates (one of them is out of town now and the other stays on the couch with friends, because he's scared). Have caught one of the friends standing out in the open, peeing on the property in front of me. I yelled at him to leave, right now, or I'd call the police . he left that moment, but is still hanging around. That roommate doesn't care. He lets people stay. 

As I understand it, I can not evict a single tenant, but have to name everyone on the lease (3 people on the same lease) and the other 2 roommates have come around to be willing for me to file eviction against them, just to get rid of this guy. I would give those 2 guys a letter from me, stating the situation and why they were named in eviction. 

But it's difficult to have a proper reason for dispossessory. 

Can him being a nuisance be a reason to file only against him? Tenants have the legal right for peaceful enjoyment of the property and neither the neighbors nor his 2 roommates have that. Have given several notices and things work for a bit, but then things slide again. RIght now he simply doesn't give a damn about me or anyone else and he's taken over the apartment. 

For the past month there's been a friends 2 cars parked on the property, taking other tenants' parking spaces. 2 weeks ago I gave notice that only residents can park there and those 2 cars would be towed, if they're seen parked there again. They were then moved to the street in front of our entrance. 

I live half a block away and drive by that street every time I come or go and I see those 2 cars every time. Once during the day the SUV is gone, but it's back the next time.  The cars are there at 4am or 8pm. I suspect his friend is living in the car (with 4 small children and wife or maybe just him), since the 2 roommates tell me that the friend is not living in the apartment, so I can't use that. 

What would you do in my situation? I'm not willing to pay him off.