It takes about 30 minutes to replace a side mirror. You'll need a screwdriver, replacement mirror, and a little bit of patience. First, open the door of your car and look for the screws that hold the mirror in place. There should be one on the top and one on the bottom. Remove these screws with your screwdriver. Next, gently pull on the mirror until it pops out of its casing. Take care not to break the mirror if it's still attached to its wire. If it is detached from its wire, you can set the mirror aside for now. Take your new replacement mirror and pop it into the casing where the old mirror was located. Replace both screws and tighten them up

It takes about 15 minutes to replace a side mirror.