Most good faucet replace will recommend replacing a gate valve regardless of its condition. The time to discover if it will work is not during a flood in your bathroom. If you have it replaced with a ball valve then check your water heater and laundry valves, too. Have them replaced at the same time with premium ball valves. Ball valve laundry bibbs make it easy to shut off the water to the washer after each use which may help to prevent floods in the future.
Use the sandpaper to remove any loose particles from the hole. It is important for the surface to be properly prepared for these types of gutter water line repair.
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.
Sales representatives must know beforehand that almost all the answers above need to be encouraging. Otherwise, there is a slim to none chance a sale is made. Besides cold call prospecting, so much of the typical sales rep's time is spent trying to make sales when a sales situation does not truly exist.
The water line repair most likely damaged your electrical outlets and lighting fixtures. Have a qualified electrician come in to evaluate and repair the electrical.
When doing the install on a water heater, keep an eye out for unconnected pipes. A commonly missed pipe is the one that leads out from the area for drainage. It is probably a recirculation pipe; that helps your water remain heated without wasting too much water.
Once you've located the water shut off, turn it off. Now, you can turn your attention to trying to contain the water damage caused by any leaking. Get towels, fans, blankets, or anything else to try and sop up water that is sitting on carpet or wood floors. Linoleum floors usually don't undergo much damage from having water sitting on them, unless there are cracks in the linoleum (often invisible) where the water can seep in. When your Queens plumber arrives, you will be one step ahead by following these instructions.