Here's a few more checks for ya

:
Engine oil filler cap and rocker cover - check for mayonnaise (blown head gasket). Check for dirty oil and carbon build up - neglect
Water bottle - smell for exhaust fumes and check it for oil (blown head gasket)
Exhaust manifold - check for cracks, this should be audible if you have the owner revving the engine and yourself listening with the hood open.
Transmission shafts - check for signs of regular lubrication on UJ joints
Diffs and gearbox - check for leaks
Tires - check wear (Irregular tyre wear might indicate suspension trouble)
Exhaust - check for rust and holes. Partly cover the tailpipe briefly with your hand while engine running and listen for leaks. Visually inspect from below.
Bodywork - check for signs of dents and dodgy repairs. Rust bubbles, rotten sills, bad scratches
Best of luck and hope you have found a good one!