How to set up Google Analytics for a network of sites?

Question

Google Analytics

Hello!
There is a company with many regional divisions. The peculiarity of the case is that the sites are clones, but on different unique domains. In other words:
1. Moscow office - moscowcompany.ru
2. St. Petersburg office - pitercompany.ru
The main task of each site in the network is to generate calls. Calls are tracked as follows:
1. Clicking on the button with the phone sends the event to Analytics
2. The call track system sends data to Analytics
At the same time, I want to set up remarketing in AdWords for the whole network (that is, in one account, be able to show a banner to anyone who visits any site).
What script to use?
1. One counter for all sites
If so, what settings should be made to the counter or Analytics so that this does not become a problem in the future.
2. Each domain has its own counter
If yes, why?
Thanks for the opinions.

Answer 1

Good afternoon,
this is called cross-domain tracking or cross-domain tracking.
You can find all the information on setting it up here https://support.google.com/analytics/answer/103434...

Answer 2

Good afternoon!
In your case, one counter for two sites is better. The setting depends on the analytics version. We will assume that you have the latest version - gtag.js.
In this case, the manual will be like this: https://developers.google.com/analytics/devguides/...
In short, on the first domain you need to write:

gtag('config', 'GA_TRACKING_ID', {
  'linker': {
    'domains': ['example.com']
  }
});

And on the second:

gtag('config', 'GA_TRACKING_ID', {
  'linker': {
    'accept_incoming': true
  }
});

I also recommend creating a filter in the analytics in the view that will show all links with domains in the reports - very convenient, the manual is here:
blog.evgenyprotasov.ru/?go=all/otobrazhnie-hostov-v-ua