depends on how cheap your getting the car for. i think your worst case scenerario is about 3 grand if you have to pull the head and have the plugs removed. i'd do it if the car was still in good shape and glowplugs where all it needed

__________________
1993 e300
1995 e320
1994 e320
2006 s500 4matic
2004 Jeep wj overland
2001 Ducati 748
2004 Honda shadow aero