I have a 1999 Deville and the front struts are bad (hard ride over rough roads), and the rear air shocks don't adjust higher with people in the back seat or a load in the trunk.
The shocks and struts are NOT the Electronic Road Sensing types.
I got prices of as high as $2200 from a local shop and $1600 from the nearest Cadillac dealer that is 50 miles away from me.
Is there a more economical solution? I doubt the car is worth putting that much money into.
Rich