There is no quick answer to your question. Here is what will happen: 1) you and the plumber will negotiate and reach a solution; 2) if negotiation fails, then the plumber will sue you, probably in small claims
court. The plumber has the burden of proof
as to the contract
because the plumber is suing you. Also, the plumber has the burden of showing a contract since the plumber did the work. It is obvious that there was confusion in the contract terms. That problem falls upon the party that should have formed the contract--the plumber. Since you already had experience with a comparable price ($75.00 per faucet) there is evidence that $85.00 per faucet is reasonable. The court will decide the case on the evidence before it. Make sure you make all your claims--such as shoddy workmanship in installation, etc. Best wishes for the new year.
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