The most difficult part of fixing a washing machine is figuring out what parts need to be replaced.
With a 10-year-old front-loading washer, a 48-inch drive belt will stretch to about 49 inches in circumference and the pump will likely not be working as well as a new one. I replaced my drive belt first and a month later had to replace my pump. Both repairs were relatively easy to make. I now have a "new" washing machine.
Always buy your parts from a reputable source, like APP. Cheap Chinese knock-offs will not last very long.