Many people who face this kind of price tag wonder if they can get away with patching their pipes. But if the sewer line is old there are almost certainly water conditioner other bad spots that will give you problems now or in the near future. A series of patch jobs isn't cheap. In the long run, it just makes more sense to replace the entire line.
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.
One other common design that is considered "washerless" was made famous by Delta and copied by several other makers. It uses little "cup" seals that fit over springs recessed in the back of the valve body. The springs press these "seals" against the cartridge and regulate the flow through little tapered openings in the cartridge. If you have one of these and it's dripping, changing these springs and seals will usually correct it. Here's a tip. Once you have the cartridge out of the way, insert a phillips screwdriver into the seal and pop both the seal and spring out. Stick the new ones on the end of the screwdriver to help guide them into place. This is especially helpful if you don't have long slender fingers.
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.
Remove the cap of the faucet using slip-joint pliers. Tape the teeth of the pliers to prevent damage of the surface. Remove the faucet cam washer and water line repair the rotating ball.
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.
Water leak detectors can keep your home safe. They can give you the peace of mind knowing that you won't come home to a house full of water. It is a lot less expensive to buy a water detector than it is to pay thousands of dollars in home repair costs.