My college nephew's 2010 i5 MBP experienced a hard drive failure. He asked me to diagnose the problem over the phone. I did so, but advised he confirm it at the local Apple store. Confirmed.
He couldn't afford the cost of the new hard drive & Apple's install charge, so I offered to do it for him.
Flawless. The only tool I lacked was the Tri-wing Y1 screwdriver. Once that arrived I printed out the iFixit instructions for a hard drive replacement for this particular MBP. After that it took about 20 minutes from beginning to end. Then the format & software install & done. Easy.
When I remove the screws I tape them next to the diagram in the iFixit guide that they correspond to. That way I don't have to remember which screw goes where when I reassemble the machine.