I'm Lucy, and I'd be happy to answer your questions today. I'm sorry to hear about your situation.
The first step is to serve the tenant with a written three-day notice to pay the total amount owed or vacate within three days. The notice can be hand-delivered to the tenant or posted on the door AND placed in the mail via first-class mail, postage prepaid. Notice would be complete after it's mailed.
If the tenant does not produce the money or leave, the next step is to go to court and file a Complaint for Eviction. The local sheriff's department will serve the notice and summons on the tenant for a small fee (you cannot serve the court papers yourself), or you can ask anyone you know over the age of 18 to do hand deliver the papers for you. The local court should have forms you can fill out to do this, but you may want to call and confirm before you go in. Some counties put the forms online so you can fill them out and print them. The clerk of the court will give you a trial date when you file the papers. If the tenant does not pay before that trial date, you will get a judgment.
Once you have a judgment, if the tenant still does not leave, you can have a sheriff forcibly remove her and all of her belongings from the premises. At that point, you'll be allowed to change the locks. And you'll be able to use the judgment to try to collect the money she owes you at that point.
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