Exhaust valves

Valves rarely need to be replaced unless burnt or bent. The process of have the valves and seats "cut" (aka valve job) at a machine shop is costly on it's own let alone having to pay someone to remove the head if you're not able to and then reassembly. Wether you rebuild the head or swap in a new (used) motor its going to end up costing about the same in the long run but that's just my opinion. Refreshing my DOHC head only cost me about $300 (half of that was machine work) but thats because I was able to do all the work myself except for resurfacing the head