How to do it better. Create one account purely for metrics and Yandex direct?

Question

Analytics

Greetings!
I would like to hear advice. How to do it better. Create one Yandex account purely for different sites (in this case, I will have a Landing Page) Metrics and Yandex direct ?
Or is it better to have one account for everything , of course, that in one place is always better.
But what about, for example, if I need a constantly new account for activation for each promotional code in Yandex Direct. And when, with different accounts, can I then observe by the metric what is happening in the poison advertising. Or is it not needed?