If it's any use I'll let you know what I've discovered from my extensive searching for Contours/Mystiques.
Tere appear to be only two categories.
1. Expensive models which are in fantastic shape. Buy this and you'll not need to drop much cash into it.
2. Cheap models that have been totally beaten to death, buried, then dug up again. These types are the real money pits.
From my experience (in Ontario, around Ottawa area) these are the only two categories. I have yet to find what I would imagine a 'reasonably priced, reasonably conditioned' Contour/Mystique.
Pay great attention to the condition and service history of the models you look at. In my experience looking at these cars used, if it has one problem it has ten! Try to get the one that was owned by the little old lady, or from an estate sale ... probably well cared for, rarely winter driven, and had full dealer servicing on-time or ahead of time. This is one bonus of buying the 'grandma's grocery car' you can find them in great shape with a little time and patience. For example, my Wife's Mystique was traded in for a Five Hundred by a little old couple who kept it meticulous!!