Thank you for your follow up.
Generally, if the costs are disputed by the consumer / customer and a lawsuit is filed, then the shop will have to disclose and provide strict proof as to how the costs were calculated or the court simply would not award such costs to the shop and generally, the consumer / customer does have the right to be provided with some type of reasonable explanation / proof, as to how the costs were incurred.
So, while I am not permitted to personally represent JustAnswer.com customers, it would be a good idea to consult and retain an experienced local civil litigation attorney and this local attorney can send a demand letter for the proof of costs and if the shop fails to provide such proof / documents, then a lawsuit can be filed against the shop for deceptive business practices / breach of contract.
You can find an experienced and skilled local civil litigation law attorney by using this established and reputable attorney information / referral websites:
When, choosing a local attorney to represent you, it would be a good idea to choose someone who has a practice exclusively dedicated to civil litigation law, has at least 10 years of experience and handled similar matters and also regularly practices before the court located in the jurisdiction where your matter will be heard.
I wish you the best of luck!