No, with Comm One Call Accounting there is no requirement that you purchase separate software for each site. Instead, you total the number of extensions at all sites, and purchase a system large enough to cover all sites.
For example, if you had 5 sites with 15 extensions at each site, instead of purchasing 5 copies of Comm One Call Accounting JR25, you could purchase one copy of Comm One Call Accounting PRO100 to cover all 75 extensions. You could load the software as 5 separate stand alone systems, or as a single networked system.
Comm One LLC Technical Support
138 E 12300 S Ste #C102
Draper, UT 84020