Thanks for contacting us.
The installations don't really matter. Licensing is just about the main domains in use. Basically you need a license per site (domain). So if you license 123.com you can have site1.123.com and site2.123.com and www.123.com using the same license. The same is true for 123.com/site1 or 123.com/site2.
This is all about deployment. You can develop as many sites as you want and using IP address or localhost will not show a Trial message.
Christopher on cc is your primary sales contact here if you got more questions about licensing.
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