W220s have had the bottom drop out as far as market price. Electronic issues along with the suspension problems are fairly common. I would expect somewhere around $12k, a bit more depending on low mileage and condition/records.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth