What is the standard mark-up on parts by mechanics?

There is no standard mark-up on parts by mechanics. The amount that a mechanic marks up a part can vary depending on a number of factors, including the type of part, the cost of the part, and the mechanic's own business practices. Some mechanics may mark up parts by a small amount, while others may mark them up by a larger amount. It is important to shop around and compare prices before you have any work done on your vehicle.