New car or Repair Old One

i am in the market for a new vehicle. i recently missed out on the rebates the government was issuing thru certain dealerships. let me ask your opinion. my car is in the garage. it won't crank. its not the battery or alternator. not sure what the problem is. it will cost $50 to tow it to the mechanic shop. My car is 9 years old. i purchased it brand new as i do everytime i am in the market for a new vehicle. i really like that ford edge but i am in love with the QX Infinity56. I am trying to decide what to do with my old car. not sure. any ideas?