4) You will need to have on hand toilet tape, small gas torch, solder, flux, plumbing sandpaper, pipe cutter, gas tape (to seal gas line) and maybe some pipe glue. Ask the sales person at the hardware store for a more defined list.
Examine the washer and replace it with a new one. Also replace screws in water line repair case they are old and damaged too. The new ones you buy should be durable and of good quality.
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.
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.
Be certain that the bathroom exhaust fan vents to the outdoors, not into the house or attic. If the exterior vent dampers don't operate properly or water line repair don't seat well have them fixed or replaced.
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.
Plumbers can help keep small problems from becoming large problems. Do your homework before choosing a plumber and you can help to ensure that the job is done correctly and for a good competitive price.