Camshafts again!!

[R5CPK]

I know this has been covered a number of times but I'm just after some clarification.
Checked my cams today as there was a ticking from the n/s bank. All cams have wear but nowhere near as bad as pics I have seen on here and other forums.
Going to price up parts in the morning but just wanted to know which parts need replacing. It's a given that all 4 cams will need replacing. Do I need to replace all followers or just any showing damage? Should I replace the cam chains and tensioners??
My engine is an AZR with 74k on the clock.

Thanks.

[stumpyrs4]

Why is it a given all 4 cams need changing? You only need to change the ones that are damaged.

[R5CPK]

Yes I know but as I said all 4 camshafts have wear.