MY FIRST POINT HERE REPEATED 100 TIMES IS:
$$$$$$$ YOU MUST BE EXPERT IN GOOGLE ANALYTICS API FOR TAPS/VISITS $$$$$
$150 for this project. Design will be provided so you'll need to work on Google Script only. Other things are not required.
If you are fimiliar with QR coding and can implement on it. then +$50 so total $200 . if your work is perfect without complaints and in time. Then +$50 so $250
So this job will give you $250 total. But make sure u have read my first point.
More details after contact. $10 if u have skype.
So total $260 now.
Good Luck. Must write GOOGLE in your PMB.