GMC Repair: Pontiac Grand Prix 1997(4-door)belt? repair, pontiac grand prix, squeals

Question
Hi. I had my oil changed recently,and they said they had a bit of trouble with a bolt on my oilpan? I could see my car shaking while the mechanic below was manipulating whatever to get my oil changed, but they managed to get it done. The same night, my car began squealing while I was driving home. It is probably just a coincidence, as I don't see how it is related, but it had never made this noise prior. My brother in law looked at it, and said it was probably the tensioner, so I purchased one, and he put it on, but my car still squeals after driving it a short distance.  Could it be something simple like me having someone change the belt? Do you know how much this should cost? I could drive it home for my b-in-law to help change, but I'm scared it may not make it, not to mention shutter at the thought of driving it with that noise 3 1/2 hours home! If I took it to a local shop though, I'm scared they'll try to rip me off since I'm a female! Thanks for any help!

Answer
It could be a belt, try to spray some brake parts cleaner on it while the engine is running to see if the noise gets better, if it does then it is the belt.

Belts range in price, but you should not be charged more than .5 hour of labor to change a non super charger belt