I am looking at a base 2009 infiniti g37 with 27,000 miles, 2 owners in good condition. Their asking price is 24,000. How much can I knock off from their asking price? I'm hoping for around 21,500 to 22,000 range. Is that achievable? I understand that this car is popular but this specific veichle has been on the lot for more than 2 months. Thanks!