Here is an update, following the Kirk's comment.
We receive the quote while the technician was on his way (he was like 5 minutes away from the house), so yes I approved: the guy was almost here and Glen said it was going to take a few hours when he came on a saturday morning to diagnose that the board had to be replaced. So I assumed it was the right price. I never received anything by email.
Understand my surprise when I see that it takes 5 minutes to replace the board and of course I called right after to understand what it is that cost 250$.
Kendra told me that Kyle will call me back to answer that question. He did: 10 days later.
Accusing me of refusing to pay a bill is HIGHLY offensive. I will never tolerate such offense. In private and in public. I am looking forward for your apologize.
I have always respected your technicians. I made sure they had plenty of water, and have always treated them with respect while on site.
I have full respect for the work anyone do, as long as done right, for the right price and in the right amount of time.
Understand that paying for a service that has not been completed is quite hard to do.