I couldn't tell you the individual price of the unit, but I might be able to get you close. We have a water furnace 7 installed in our new house. The initial quote has the series 7 at 37k and the series 5 at 33k. Here's what's included in the price:

7-5 Hot water assist

7 Variable speed compressor

5 dual speed compressor

7-5 insulated cabinet

7-5 anti vibration base pad

7-5 T-stat TPPC32U01

7-5 Auxiliary Heat (free with unit price)

7-5 Performance and refrigeration package

5 Intellistart

7 Variable Speed Flowcenter

7-5 Aprilaire Media Filter (model 1201)

7-5 50 gal preheat tank

7-5 duct system

7-5 controller for 3 zones

all bathroom and duct fans.

Obviously you wouldn't need many of these things (controller, preheat tank, bathroom fans, duct system, thermostats) but I don't have line item cost for these and can't separate them from the quote.

Thanks for the response. You're right, my costs will be less since I just need to replace the central system.