It may not have been have been a factor, but the Prius is a larger car than a Sunbird.
As to diesel in the US, prices in some areas are down around regular gas. It is cheaper in southern California. I pass 4 stations at least on my 30 mile commute that have diesel. It still costs more here, but heating oil might still being affecting demand.
As for the OP, used diesel seems the way to go, but all I know is that the UK has a better selection in that regard.
I had been trying to sell it anyway, because the driver's seat was so shaped as to be giving me back problems.
I don't know what the guys at Pontiac were thinking in that era. I had a '97 Grand Am that was ergonomically wrong for me. I guess it might fit other people, but it sure didn't fit me.
As it was, the damage estimate was about $4300; the car's book retail was $2500. The insurance company told me the salvage value was $450. I took the $2500 less the $450 and donated the car to the local school for their shop kids to work on. They insisted on paying me the salvage value, then sold the car after they played with it for $995 to one of the students. Win - win. The profit they made went into their Power Drive program, which is sponsored by Omaha Public Power District and is a program where students build and then race electric cars.
By the way, the title never left my hands until the school got it, so the title is "clean" and not marked that the car was totalled. The new buyer was told, though.
That sounds like it worked out really, really well.