My girlfriend inherited her grandmother's house. My girlfriend's mom has been living in the house for several years, rent, lease, and contract free. We've told her that the Trust that the house is running on is dwindling, and she is going to start having to pay rent. She doesn't have a job, so she has still yet to pay rent.
Just yesterday, we found out that she's been stealing stuff from the house and selling it to pay for gas and cigarettes, and that is obviously the last straw and we want her out. We don't want to file charges against her for stealing (although, we should). We want to give her as little of a notice as possible, so she doesn't have time to scavenge the house for more stuff she can sell prior to leaving.
My question is, how much of a notice are we legally required to give her before we consider it trespassing, and change the locks?