My 87 year old mother called John Dahl about a clogged sink and got an estimate around $150. The plumber took 3 1/2 hours - replacing the p-trap & sink stopper and charged her roughly $550. Assuming the pipes needed to be replaced, it's NOT a 3 1/2 hour job. When I called the office to ask about the bill, I got a number of convoluted explanations - "maybe the plumber needed to climb on the roof to snake out the drain though the vent pipe" (he didn't)- and an increasingly rude and defensive attitude. It became clear that they had no valid explanation of why it took 3 1/2 hours to do a simple do-it-yourself repair job, nor were they willing to adjust the bill. I can only assume that the plumber was poorly trained and/or did not have the necessary parts on his truck to do the job quickly. Perhaps he felt an 87 year old woman living alone would not think to question a $550 bill. My family - three households in the Bay Area - won't be calling them in the future.