The rough number I use for Chargepoint installs is $6000-$7000. Yes, they are the Lexus option in this market.
But you can get an EVSE, even for a retail usage scenario, for FAR less money.
I have all of the options written up here, starting with the cheapest and working up the price ladder to Chargepoint. Personally I recommend one of the Clipper Creek chargers.
public charging station advice for retail businesses - www.ElectrifyAtlanta.com