We had problems with our kitchen sick/garbage disposal. The kitchen sink was regurgitating water after running the disposal.
We had a technician come out 2 days before our wedding. He went to get a snake to run through and put ice & dish detergent down the sink. When he left, it was not regurgitating and charged over $400 (since he had to leave to go get supplies--even though we told them the issue before the appointment. Shouldn't you have that included in your supply truck? It's pretty standard for a sink issue).
We were gone 2 weeks after on our honeymoon and when we got back, the issue was still not fixed. They sent out another technician to take a look and when he left, the problem was worse than before. Now the sink regurgitates even when you're not running the water and we had a leak through the ceiling to our downstairs (right below the kitchen sink).

I called and asked for a refund and told them I had no problem paying for the service calls but they refused to give me my money back because they said:
A) I was calling 3 weeks later (even though I explained I was on my honeymoon) and B) When the first technician left it was "fixed" and he ran the disposal to prove it. No, it's not fixed and we did not touch it for 2 weeks after since we were gone. The situation is now worse and we are out over $400.
When I explain all this to the owner, he said it could be a bigger plumbing issue and they "did their job because the disposal was working when the first technician left." That's just not good business practice. Stand up to your "100% guarantee policy." If you can't fix the problem, charge for the time/service call but don't pretend like it's out of your hands now.

I would NOT recommend Mr. Handyman and will not ever call them again. My husband is in the real estate business and he will never recommending them either. Very disappointed.