I had a 2000 Grand PRix SE, with around 125,000 miles when I bought it. I believe I paid around $5000 for it 3 years ago. THe only major problem I had was bad wiring. I had a few annoying problems with my A/C blower (damn thing wouldn't shut of...ever), and some other minor stuff. Nothing too serious, it should run good if you take care of it.
And yes,$7000 is way too much money. I wouldn't pay any more than $5000.