Question: I purchased a new vanity and must remove the old one however the pipes don’t have valves to shut the water supply off and I need a supply of water to the rest of the house until the new vanity can be installed. How do I plug the water pipes?
Answer: What I would do is, cut the water to the entire house. Remove the old vanity which in your case, will involve cutting the water pipes that supply the vanity faucet. Once the pipes are cut, simply install water stops onto the cut pipes. Now you can leave the stops turned off as long as you need to while waiting for the vanity to be installed.
If you have never done any plumbing before, you may want to consult a qualified person to help you remove the old vanity as, while installing a water stop may not be rocket science. An improperly installed water stop can be very messy and result in many dollars in water damage.