I haven't had to use a plumber at a house since I am a renter, but I have had to call one from where I work, and we have always used Jeff the Plumber. My sister-in-law's office also uses Jeff the Plumber. Neither of our workplaces has had any problems, the plumbers (who aren't always named Jeff, by the way) are skilled, honest, and trustworthy. They don't overcharge or try to price gouge.
PROS: Honest and skilled
CONS: none
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