Christine Credit score.
I know credit score (or credit rating) as the trustworthiness for getting a loan, like when you want to buy a house they want to check if you're likely to be paying it off. Normally if you would rent a small apartment, or even a room with a landlord/-lady, it wouldn't be checked, would it? I don't think they are even allowed to here, only banks can.
Or do you mean you built up debt on a credit card and first need to pay that off? Perhaps not, since the solution for that would also be trying to get a better paying job, although it will take longer then until you can move out.