I agreed with a plumber to come in for a small job on a short notice. He estimated the work to £135. Unfortunately, when he came in, nobody has let him in, so no work has been done.

Now, he wants to invoice me for full amount, as he claims it a lost profit. I offered to pay part of the sum for his lost. However, the contractor still wants the full amount!

Before coming in, he said "this is my best estimate, without seeing the problem and if that's a quick fix", but did not mention the call-out fee.

Am I obliged to pay? Who is in the right here?