Here's what NADA says about it:

MERCEDES-BENZ (German)
1985


Body Style: Sedan 4 Door 190d
Model Number: DB22
Weight: 2,700
Low Retail: $2,900
Average Retail: $4,050
High Retail: $4,975


I think maybe the high mileage would put it between "low" and "average"

__________________
Nello Tare

1982 300D (266,001 mi.) looking and running great

Previously owned:
1976 450 SLC
1983 300D
1976 300D
also
1982 Jaguar XJ6 (loved, but gone)