"he quoted me what I thought was a very reasonable price."
When all the drains in your house or either slow or backing up, you know you have a mainline problem. My normal plumbers do not do mainline and recommended All Drain.
I called them Thursday evening before the holiday weekend expecting to be stalled. No, they had a man out the next day. He showed up on time and was very pleasant. He did not talk down to me nor dismiss my assessment.
He looked up the sewer line and realized that it took interesting turns and was longer than what he could do himself so told me a second man would be needed. I saw $$$$, but he quoted me what I thought was a very reasonable price (based upon internet searches).
Within 1/2 hour, second man was at site, and they lugged this 300lb monstrosity down my steps(I felt bad; they didn't complain). After they finished and was lugging the machine up the stairs, my husband, who had just gotten home, told them not to worry about cleaning up. They told him it was too late. The basement was clean, but they did suggest we sterilize the floor. Bleach is a wonderful thing.
After running water through all the sinks, the first man then handed me the bill. It was lower than the original quote. We gladly paid it. It has been over a week and the drains are doing great.