Should i get put more money

I have a 2000 nissan maxima with 289,000 clicks , rusted, fully loaded 25th special addition i paid 3000$ for it like 3 years ago and must have put in over 3000$ in repairs over the years, right now it needs summer tires, brakes , every time i turn left the steering wheel or left driver tires makes loud grinding noise.. And now i have a friend at work selling her 2002 nissan sentra ex with 129,000 clicks runs well has a cracked bumper and the a/c just went but other than that runs excellent, with summer and winter tires for 1000$ !! Should i buy the sentra? And how much would someone give me for the maxima? Thanks for your opinion!