That diagnosed big expense coming up, I agree, means it is time to get another car. My point is, to be sure a car is 'acceptable,' a mechanics evaluation is a big help. Nothing wrong with costing out which of the acceptable ones is the best buy if you are lucky enough to find more than one.

In 60 years of driving, I have had a variety of cars. All were used, from one year to a few years old, except one I bought new when I made a lucky guess on the stock market (1972 BMW CS, my son still has it). Only one bad one, a smaller Japanese model on which the motor blew after I had it for about a year.
I have an inlaw who has an older Park Avenue, and had one previous to it, and never had any serious problems. She also was able to find good used ones. Her tastes must be similar to yours.