Preventive Maintenance and an uncooperative customer.

I have most of my sensors hooked up. I've got one up there, outdoor temperature sensor, and I've got the return and supply hooked up inside on the registers and the return. And this is a 5 ton, but the temperature out here is kind of low, 76. It's probably more like 70. I had that in the sun. But most everything seems to be in line with this one. He complained about his electric bill, but he had it set on emergency heat. I'm going to leave out my conversation with this homeowner, but I'm finding a capacitor that is bad during a preventive maintenance. He said he wasn't going to pay for it after I changed it. So I put the old one back on, and then he said he's going to pay for it. So I changed this capacitor three times, and here's the deal. I was only charging him $40 because I found it during a preventive maintenance. He gave me a hard time about that.