Pro Plumbers

For many centuries, lead was the favoured material for water pipes, because its malleability made it practical to work into the desired shape. (Such use was so common that the word "plumbing" derives from plumbum, the Latin word for lead.) This was a source of lead-related health problems in the years before the health hazards of ingesting lead were fully understood; among these were stillbirths and high rates of infant mortality. Lead water pipes were still widely used in the early 20th century, and remain in many households. In addition, lead-tin alloy solder was commonly used to join copper pipes, but modern practice uses tin-antimony alloy solder instead, in order to eliminate lead hazards.[13]
In the United Kingdom the professional body is the Chartered Institute of Plumbing and Heating Engineering (educational charity status) and it is true that the trade still remains virtually ungoverned;[36] there are no systems in place to monitor or control the activities of unqualified plumbers or those home owners who choose to undertake installation and maintenance works themselves, despite the health and safety issues which arise from such works when they are undertaken incorrectly; see Health Aspects of Plumbing (HAP) published jointly by the World Health Organization (WHO) and the World Plumbing Council (WPC).[37][38] WPC has subsequently appointed a representative to the World Health Organization to take forward various projects related to Health Aspects of Plumbing.[39]
plumbers must be asked directly what they charge hourly and if that is in addition to a service charge. The two are separate and I think they have gotten away with outrageous charges because of the potential of water damaging homeowner structures.   I had a plumber (not Home advisor) come and replace a part in my kitchen sink that was under warranty---the spray nozzle had been leaking...He charged me $85.00 for 15 minutes of work and I will never use Mr King again. 
Help! The toilet won’t stop running. It’s a bummer, sure, but it’s something you don’t need to call your plumber about. In fact, DIYers should take note that it’s a quick fix that will cost you just $5. For instance, your handle might just be sticking, which can be solved by spraying some lubricant where the handle meets the porcelain. Ready to DIY? Here’s how to fix a running toilet.
I had called Ben Franklin to fix a pin hole leak in the meter horn. Booking an appointment was very easy and the crew (Sid and Brandon) showed up on time. They quickly found out that a stop valve was not working and had to be replaced as well. Sid clearly explained my options and the charges upfront. He dealt with the city for water shut off, went about the job in a quick and efficient manner. Sid was very professional and explained clearly what he was doing. He patiently answered all my questions. Brandon was very practical and frank. As they were finishing up (I had to leave the house for an hour) they spotted a leak in another valve and fixed that also. I thought it was highly ethical of them to do so. Thank you Sid and Brandon!
I think it is rather rude and a bit dishonest for people to not divulge their total fees upfront, an of course we should know to ask. But the normal person wouldn't know the questions to ask until they are burnt once like this, and then there still could be costs for walking up stairs or charge another service call if they need to go somewhere to use the bathroom and come back. THAT ISN'T A QUESTION I WOULD THINK TO ASK.
Plumbing reached its early apex in ancient Rome, which saw the introduction of expansive systems of aqueducts, tile wastewater removal, and widespread use of lead pipes. With the Fall of Rome both water supply and sanitation stagnated—or regressed—for well over 1,000 years. Improvement was very slow, with little effective progress made until the growth of modern densely populated cities in the 1800s. During this period, public health authorities began pressing for better waste disposal systems to be installed, to prevent or control epidemics of disease. Earlier, the waste disposal system had merely consisted of collecting waste and dumping it on the ground or into a river. Eventually the development of separate, underground water and sewage systems eliminated open sewage ditches and cesspools.