There are other skills plumbers need aside from being able to work with water. One of the most common things that a faucet replace on is fixing water lines.
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.
The first thing you need to do after leakage starts is to shut the water supply before you remove the faucet. You can either shut the valve in the sink or the main valve of your home. After that ensure that the water in the water line is drained and also the air pressure s released. This will also help in saving a lot of water that might have been wasted due to the leakage.
Blisters in asphalt or felt roofs only need to be treated if they contain water or have caused the roof covering to leak. Press the blister to check if moisture is expelled. If so, it must be sealed with a patch.
18. When using an electronic chart plotter do not use the waypoints at the harbour entrances. Anticipate the direction from which you will be approaching and chose a waypoint which will help you to water line repair eyeball your way in.
Turn the water off at the main shutoff valve at the street. You should be able to take a pair of pliers(or your bare hands) and turn the valve at the water meter to shut off the water to your home. Once you have shut off the water you can cut the pipe around the leak and make the repair.
The plumber you hire does not normally do heating but will do hot water heating or in floor heating in the house. Some places you can use the water heater for both domestic hot water and for in floor heating if the heating is a secondary heat. Check with your local plumbing codes on this to be clear.