The $135 wasn't a dispatch fee. The dispatch fee was $29 and was waived because she accepted the $135 diagnosis and repair fee.
The funny thing is the $135 was what I would have charged even if I didn't know what the other guy had charged. At the time this was my minimum flat rate diagnosis and repair fee.
It was printed in my flat rate book. It was just a coincedence that it was the same as the other guys charges.
I found the loose wires right away but didn't fix them or mention them right away. I went ahead and did a quick inspection of the rest of the home and noted the problems I found.
I then gave her a price of $135 to diagnose the problem and told her it included minor repairs such as tightening loose connetions. I also gave her a list of the other problems I found with the prices to make the repairs and let her know the $135 would be credited towards the repairs if she had me do them.
At this point she could have opted to pay the $29 dispatch fee and send me away.
She accepted the $135, paid me and then sheduled to have me come back later and complete the other work. I tightened the connections in the panel and let her know what I did. I credited the $135 back after completion of the other work.
She was very happy that I let her know about the other problems she had been in a house fire when she was little.
By the way I would have tightened the loose wires in the panel before putting the cover back on even if she hadn't agreed to the $135. I wouldn't have felt comfortable leaving them loose.
Usually when I get to the customers home I don't quote a price right away. I'll pull the panel covres and do a quick inspection or evalutation of the home's wiring. Often times I'll find the problem while doing this and then I know how much to quote. It's easier to sell them on the price after they've seen how hard you've worked.
If I don't find the problem while doing this it at least gives me an idea of how long I think it will take to find the problem.