On the 2.3L 4 banger I’m seeing 4+ hours labor to replace the PCV valve. The intake manifold has to come out. So $710 actually seems pretty reasonable. If I had that car and the only reason to replace the PCV valve is b/c the odometer is hitting 100K, I’d defer that job until either a pcv related symptom appeared, or the intake manifold had to be removed for another reason. the part itself is less than $200 $20, but 4 hours labor, wow!
One idea you might check w/the shop tech : Is it possible to inject some pcv valve cleaner into the valve via the breather hose? Usually when the pcv valve develops problems, it is b/c it is gunked up. I’ve had very good success cleaning mine when this happens. I just soak it a little gasoline. The pcv valves on all my vehicles have always been very simple to remove, just pull them out of a hole in the valve cover is all. 5 minutes max.
One take from this: Good idea when buying a car to check the parts and labor cost of common replacement items like pcv valve, brake pads & rotors, struts, water pump, spark plugs, etc, before deciding on which make & model to choose from.