I just had my pipe under the sink unclogged and new pipes put in $600.00, then they flushed out the pipe from under the sink to the outside pipe $700.00, Total of $1.600.00, I thought that the price was high, I got the plumber from Home Advisors, not sure they had to do all they did but they said I needed the work done. The same evening hike using the dishwasher I had a leak in one of the pipes they put in, they came back the next day to fix it. Don't know if I will use them again.. They were K&D kitchens.
Sometimes a faucet leak can be stopped by replacing the rubber washer at the end of a faucet stem or cartridge. This is a more common repair on older fixtures when things were built to last and designed to be able to be maintained. Other times the whole stem or cartridge needs replacement or the bibb seat deeper back into the fixture needs replacement. That leads to matching up the right components and often times making a trip to the hardware store or plumbing supply house necessary due to the many varieties, makes and models of faucets. My advice is to make sure your Plumber has faucet repair kit on their truck before having them come out to assess the issue.