I haven't personally done so, but I did help my parents file an eviction suit against a tenant. My parents made a mistake renting to this guy who someone else brought in without my parents meeting him before renting to him. It was kind of a complicated situation as they were renting out individually without a master tenant, even though they didn't live there like it was an owner-occupied room rental. He ended up driving out 3 of the tenants who couldn't stand him, and the final guy who got along best with him didn't have a problem leaving when given a notice.
However, he rather stood firm. Apparently on the second day he was a tenant my mom came to meet him and accidentally saw him in a state of undress because someone else opened the door. Once they sent him a notice a year later he started going crazy that he was going to sue them over that "harassment" from a year back. He also started going off that he was worried about lead paint because the laundry room had paint that was bubbling and he claimed he might be able to sue for hundreds of thousands of dollars for exposing him to lead. I was kind of skeptical since I assumed he wasn't a 3 year old who chewed on peeling paint chips and he would need to show lead in his bloodstream to prove he was damaged, but I guess he thought it was his trump card.
He left some awesome answering machine messages. They were total stream of consciousness stuff. He seemed to be somewhat mentally unbalanced. He would shift from conciliatory to angry and accusatory. One time my wife answered the phone at my parents place when he called, and she rather tore into him in a way my parents didn't quite do and he seemed a bit scared. Eventually he met me (he seemed to think my wife was my sister) and I let him know we weren't scared of him, he had no legal right to stay there, his threats of harassment and lead exposure wouldn't hold up in court (and my parents' insurance company would provide lawyers to defend against his bull) and if he didn't leave we'd be forced to sue him to leave.
My mom didn't take the threats very well. She contacted her insurance company about all this, and they said that if he tried to sue them they had attorneys who would fight it and she was covered up to $750,000 anyways. And she wanted me to work of sending him a legal notice to leave or face a court-ordered eviction. I bought a book from Nolo Press on the California eviction process. It was much better than trying to figure out everything by myself as it had detailed instructions on how to fill out the forms, how to file, and exactly what forms needed to be filled out.
So I had fun trying to figure out exactly how to fill out the standard forms. We took them to the court clerk to file them (which actually cost a couple hundred dollars), and then found a process server to send these to the tenant. I could have done it myself since I technically wasn't a party to the lawsuit even though I mostly prepared the paperwork. The server's fee actually included 3 tries to serve in person followed by a standard mailing (which delays the schedule) if it didn't work. Apparently the tenant just opened the door the first time, the server said "You've been served", and dropped it in front of him. I had that book and had researched all the stuff including default judgements (for failure to respond), going to court, scheduling an eviction with the sheriff's civil process division, etc. It seemed kind of daunting but I was kind of psyched about tossing this guy out who seemed like a total nutjob.
Then he apparently got scared once actual legal paperwork was filed against him, and he caved. I doubt that he would have been able to come up with the proper response within the five business days he had to respond, and we found out he never responded and we could have filed for a default judgement. He was gone within 15 days but we could have requested a default judgement at any time. And at that point he was no longer making threats about suing anyone.
It was kind of scary, but in a way kind of exciting doing all that stuff.