The work does not seem to pay well though. They expect me to help them for free.... ;-)
Like me, I suspect you're not charging up-front, but rather, you get to that after services have been rendered. After they’ve seen you press a few buttons and voila… everything’s fine again… that’s not the time to negotiate a fee for services rendered.
I'll suggest next time, when you first arrive for the service call: size up the panic, desperation, and hysteria in their eyes... notice the trembling of their fingers while they're wildly fumbling through the operator's manual (which may or may not be the appropriate manual, or group of manuals)... notice the pile of changed out batteries and apple box of rummaged through patch cables... notice the family pet cowering in a corner or hiding out outside (with a facial expression of: "I don't know what's going on in there, but in-there is a bad place to be right now.") Notice what meal was left abandoned on the kitchen table... if it's 4:00pm when you arrive for the service call, and 1/2 eaten breakfast or last night's dinner is still on the table, you can do the math to determine the magnitude of the crisis at that point. Take special note if there's a significant other locked in the bathroom and muffled sounds of sobbing are audible through the bathroom door. If conditions seem promising, start in on a monolog of how things are tough all over (baby needs new shoes) and “taking time off work… might look bad to the boss and you'll have to make good with the boss some-way or another”… sick relative… blah, blah, blah. Initially their eyes will start to glaze over, but after a few tens of seconds, they’ll glance over at the teevee to confirm that the screen is still otherwise blank except for the flashing red “input” lettering in the lower left hand corner of the screen. When they make that glace, seize on the opportunity to ratchet it up a notch and really lay your sob story on hot and heavy… Christmas coming up, higher than usual heating bills… likely gonna be a really skinny Santa at your house this year… “don’t know how to break it to the kids”… maybe pull out your billfold and let the moth in the empty cash compartment fly free… maybe mention that in your opinion, things were better when our country operated more-so on a cash basis. Sometime during all of this they’ll likely suggest that they want to make this right by you… bingo… you’ve struck oil and can quit drilling… except to press that service calls are seemingly becoming a thing of the past… most folks just “buy new” when there’s a problem like this… and you don’t know for sure, but you suspect that replacing all that stuff would be BIG BUCKS… “But whatever you think is reasonable will be fine with me… and I‘ll get right on it.”