How much should a replacement HVAC system cost in the DC area?

Has the "SEER 13" efficiency standard greatly increased the cost of AC replacement (a lot of the other questions I see here were answered before SEER 13 was in effect)? I live in the DC area and got a quote for $7500 for complete HVAC system replacement including installation (no ductwork, for my 2600 sq ft house). The system is rated SEER 16 and qualifies for the $1500 tax deduction. Am I getting fleeced or is this about right?