Not necessarily. Your wish is to break the contract you currently have, and the price for that is to grant my wish of having a contract with you. A contract for a contract sounds like a fair exchange to me.

[He can handle the actual breaking of the current contract, all he has to do is offer something of similar value as a payment to the person currently holding Lovecraft's contract.

...which probably means a 'free' wish for Fitzgerald, but Watanuki can deal with that.]