I don’t think you’d be allowed to change locks but isn’t there more chance of her stealing your computer and other stuff if she does have the key? How would she take a computer if she wouldn’t be able to unlock the door? Maybe I am not understanding the whole set up but how and why does she have a key? Does she actually go into people’s places in their absence? Hopefully rental office would look into it. Unbelievable.

I think you might need a co-signer for an apartment. Or find rental situation that wouldn’t look into credit history or expect employment such as private rental (someone just rents one room out not like apartment complex ). I have never lived with roommates but my daughter has some awful stories to tell (and some good ones). But honestly without income your options are limited. You might need some help from welfare system. I’d look up social security offices online if they offer anything.

When are you done with grad school? Do you have any family or friends you can stay with while finishing grad school? You mentioned people who helped you out before.