You can add an unlimited number of sites to your AWR subscription.
Keyword units consumption depends on other factors:
number of keywords
the number of search engines in your project
project update frequency
Within one project, you can add one website as main and 50 other domains as competitors to be tracked for the same set of keywords, and this will not impact the units spent.
Tip: You can use the Top Sites report to increase the number of relevant website competitors:
Do you have any other questions? Don’t hesitate to get in touch and we will keep building the FAQ.