$125 to show up and first hour, $75 for additional hours. Sliding scale if it takes 6 hours maybe give em a break.

I like to walk out of a repair with $200-350 or it's really not worth my time. House calls are potentially a major pain in the ass and you never really know what you are getting into. It's impossible to bring all the parts you might need and most homeowners are terrible at describing issues. In the event that it's something really simple pad it out with a cleaning/light bulb check to get to the two hours.

It's really up to you. But I always make it clear that I can't diagnose issues on the phone and that it's gonna cost $200-400 most likely. You can feel em out pretty quickly and see if they are too cheap to deal with. Your time and skills are valuable.