Oil change service near Palm Springs, FL

I'm a female, so guess he figured I was stupid! Went for an oil change, he told me I needed a serpentine belt! Everything would be $100.00, I have bought them before, my truck is a 2001, so, yeah, I've bought them! This guy left and went to advanced auto parts and put it on in 5 minutes. When he was done, he went into his protective cubby, holding my keys the whole time, seemed odd. Then I saw my bill! $164! I know he paid $34.00 for the belt, he charged me $100.00 + tax for JUST the belt!!!! When my husband went to talk to him, he ran into his cubby and started screaming and cussing at him, said crap like, he was gonna f his mother. Etc.. When he came back, he was furious! I tried calling, he refused to give me his name, then proceeded to curse me out, I plan on contacting the BBB and small claims! Any repairs over $100.00, must have a written detailed estimate which I would have to sign! He is so unprofessional, he told me he can charge what ever he wants! Sorry dude, in this country we have laws to protect the consumer from rip off artists such as yourself! Please! No one go to him! It got so bad, I had to call the cops! Owners name is christian seigel. Buyers beware of him!!!!!!