The overall rating reflects the current state of the app. It accounts for all app reviews but prioritizes the most recent ones.
Well, firstly, you can't actually download the app. It takes you to a link to set up an account. Secondly, no one can give you a price quote unless you give them your phone number. It doesn't matter if you're mute. Unless you speak to them over the phone, they won't give you a price quote.