With all due respect to HomeGuru, I believe he is incorrect.
Without knowing more about the contract conditions, it is probably a valid contract. There are very specific conditions that would allow cancellation (such as the 3-day rule on door-to-door).
However, HomeGuru is correct in advising to dispute the bill to your credit card company.
I suggest doing the following:
1) Send a letter (certified mail) to the 'merchant' (the contractor). In that letter, detail how you were mislead and your dispute. Ask that they issue a credit to your card account. Ask them to respond to your letter within a specific timeframe (10 days from receipt).
2) When you receive your credit card statement, send a letter to the credit card company disputing the merchant account. In your letter, detail the dispute and that you have tried to resolve it with the merchant without satisfaction. You need to send this dispute letter within 30 (or 60, I don't recall) days of receipt of your statement. It must be in writing. Look at the back of the statement for the specifics and the address to send to. Do not send it with your payment.
3) Upon receipt of your letter, the credit card company will freeze the charge on your card. They will also investigate the charge for your dispute and, hopefully, upon completion do a 'charge-back' against the merchant account and credit your account.
Hope that this helps.... and you were smart (or lucky) to pay this with a credit card. Payment by any other method would have left you in your 'contract'.
Judgment Recovery of Texas
[This message has been edited by Halket (edited June 29, 2000).]