Originally Posted by StephenVA

Standard shop practice: if you have to touch it, replace everything.

In a DIY world I would recommend one of two approaches:
1. Replace everything if you are planning a long term relationship.
2. Replace the belts, test for looseness and listen for bushing failures on the idler but I would replace the two tensioners (one on the AC side and one on the Alternator/WP side) as they are easy to gain access to and have the higher wear/failure rates.

NOTHING is worse than doing it twice. Besides, winter is coming (here in the top side of the world) and everything that is on the edge seems to fails when it is cold and miserable outside. (Example: Ever tired knocking the ball joints and spindle off a vehicle when it is snowing? NOT PRETTY )