The filing fee alone for a claim not exceeding $250 in Cook County is $119.00. Is the time and effort of trying to collect $250 really that worth it? You will need to prepare a complaint, file it, make sure it is properly served and then appear in court and prove your case. And just because you get a judgment doesn't mean you will automatically get paid.
Do you really need the money or is it just the principal. You should consider it a lesson in roommate relations and move on.
Oral contracts and contracts "implied in fact" by the parties conduct are as enforceable as written contracts, although they're somewhat harder to prove. Here, with your other roommate's testimony, the utility bills, and your own testimony, that's not really the problem. Your roommate's excuses aren't defenses to her agreement to pay her share of the costs.
But this is a cost-benefit analysis, and the benefit is quite small, and the cost is quite high.
If the filing fee is really that much for a Small Claims court, then I agree that this may not be worth the effort. I would think that you'd be able to add that fiing fee to your claim, but you'll still have to front that cost, plus spend your time pursuing this, plus spend more effort, if she doesn't pay up voluntarily, collecting the judgment by garnishing her wages, levying her bank account, etc.
Another option is to post what a deadbeat she is on your Facebook page. Tell the truth, and stick to the facts of the situation and your opinions of her conduct, and you'll avoid defamation exposure.
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