Usual things to look for:
Head gasket - what's the mileage ?. If the gasket has been done, was it replaced before the head got trashed ?. Check for small bubbles of air in the expansion tank - the gasket can go between one of the cylinders and a waterway, so you don't get any mayo, the compression just forces the water out ! (mine would ony blow water when driven over 70mph !)
GS spec may have ACE - check that the hydraulic pipes were replaced under the recall prog.
Same applies to SLS (self-levelling suspension, normally only on 7 seaters) - does it work ?, does one side sag after a while ?
Flywheel - some of the early ones have been known to self-destruct, should have been replaced a long time ago under a recall.
ABS pump (pasenger side of engine bay) - should have two round metal discs screwed on top with allen bolts, again, done under recall.
Check all the electrics, will probably only have 2 manual sunroofs though.
Steering box seals can let go, don't think you can replace the seals - so new/recon box needed.
Any other q's, please ask.
Jim