The plumbing courses cover all the aspects that you will be required to deal with as a bathtub repair. You will be taught about the basic aspects as well as about health and safety issues and sanitation.
When you get to the house stand if front of the toilet and locate the water shut off valve. Should be down below the toilet on the wall. Just turn it off (righty-tighty) completely and flush the toilet. All the water should have left the tank, well at least most of it. If there is remaining water line repair get it out with paper towels or a rag. The important thing is that no more water came in. If it did then your valve is not shut all the way or not working and you need additional help.
When trying to locate a plumber, be sure they have had proper training. There are three types of plumbers and they are classified by the amount of training they have. An apprentice plumber receives training through a local union. They follow an apprenticeship program for about three or four years. They learn through on-the-job training and some classroom structure. An apprentice plumber does get paid for on-the-job training.
Sales representatives must know beforehand that almost all the answers above need to be encouraging. Otherwise, there is a slim to none chance a sale is made. Besides cold call prospecting, so much of the typical sales rep's time is spent trying to make sales when a sales situation does not truly exist.
One tip is to avoid hiring a plumber, who is a part or who is representing a company. They usually work on a commission basis. The company usually has a flat rate for every plumbing service and the plumber's commission will be added up to the company's charge. This is one of the main reasons why some plumbers charge you with a ridiculously high amount of money for their services. Opt for freelance water line repair plumbers instead. They work for themselves, so the price is usually negotiable.
And the way to know what's sufficient? Well, until the work is done an the bill paid you won't know for certain, but this is the best that can be suggested and normally works very well.
Especially with older plumbing systems, a leaky pipe is like an alarm, signaling that other pipes may also be on the brink of failure. To get a grip on whether your plumbing system can last, a professional plumber may send a remote camera through your network. If any pipes are about to break, the camera will give you a heads up. If your entire plumbing system is outdated and weak, it may be best to simply replace the whole thing. Although this can be a costly enterprise, with a price tag of at least a couple of thousand dollars, the upside is that a new sewer line will reliably perform its duty for decades to come.