Date registered: Dec 2005
Vehicle: W211 E320 Bluetec R129 SL500 - $1300 car ........ Ford F350 6l
Location: CA Bay Area
Mentioned: 9 Post(s)
Quoted: 1070 Post(s)
Figure out the size first. Not too many people are satisfy with size of C so E is next choice.
Those years have very good years reliability wise so you should have good choices.
4-Matic are harder to find while wagons are rare and sell at premium.
Each model section has common issues sticked on the top, so it easy to find as Fly advised you.
Welcome to the forum and good luck in your search.