Visa or Master Card!
This. So. Much. This.
Since the question is ultimate tune up and it's your money. . .
In addition to O2 sensors and spark plugs. . . engine oil, oil filter, air filter, PCV, spark plug wires, (if equipped) distributor cap and rotor, ignition coil, fuel injectors/cleaning depending on mileage and spray pattern, clean battery terminals, replace cables if corroded/cut/etc, clean engine and chassis grounding points, flush cooling system, thermostat, flush brake system, change diff fluid- gear oil, RTV, gasket if desired, transmission fluid, trans filter if equipped, t-case oil. Find all zerk fittings and lube 'em up.
I'm sort of a neat-nik, so anytime something is removed it or the area gets cleaned. Remove a bolt- it gets cleaned on the bench grinder's wire wheel and depending on the application the head gets painted and threads kissed with anti-seize.
I'm also a fan of performing coolant pressure tests, engine compression tests, and cylinder leak-down tests on used vehicles I buy. But, I own the tools and wouldn't necessarily recommend paying a shop for these services if everything seems ok.
