I need to change the harmonic balancer seal and possibly the balancer as well, and I would like to know how much money are the parts worth roughly, and how much of a pain in the a*** is it to change the parts out, or is it worth my while just sending the car to the mechanic’s?

The car is an AU3 6 cylinder.

Any info would be a great help.

the tool to remove the AU balancer is about $250.
you should be charged 1.5 hours MAX even at $100/h is cheaer then buying the tool.
If you buy the parts $15 for the seal a few hundred? (not sure) for the balancer.