I called at 7pm on a Friday night, and Mark answered and scheduled service call for noon on the next day - Saturday. This is the 4th time that we have used Mark for our very old (1983 original with house) air conditioner. Our home warranty company said it was dead and needed replacing over 4 years ago. I call Mark for second opinion, and he got it running again in one visit. It has had some issues, but he manages to help get it back working each time. I know it will need replacing soon - but so grateful that Mark is willing to keep working and fixing it, so that we are not out of pocket the enormous bill for a whole new unit. Fast response, reliable, and very nice. Highly recommend him - honest guy, willing to save you money instead of sales pushing new unit.