I have two WordPress multisites under one domain - city-x.domain.com and city-y.domain.com. domain.com is a landing page where you select your city, and a cookie will redirect the user to that city on subsequent visits.

I'd like to be able to track the number of hits on all pages on domain.com, city-x.domain.com and city-y.domain.com separately and combined. How is this

On a side note, I've heard that GA underestimates hits. As this is important for advertising purposes, is there a better free service?