John,
You didn't say what part of country the work was done. You mentioned you received and gave the go-ahead on an estimate for the type of work your job site required. Perhaps it was the amount of time used to do the job that surprised you. You have to ask yourself if the job was done to a professional standard and will hold up under normal usage? If so, then you should be happy, the company did its job in a professional, quick and timely manner for the price agree by you. Still I would say it was fair amount for a job well done.
Rusty Bates
(SNIP)