Sofia deployment is basically the same whether you migrated from Vision, installed sofia from scratch, or plan to use sofia in the Cloud.
You may use sofia in the Cloud with a single site. A site may be comprised of single floor, a multi-floor building, or a multi-building campus. Sofia also allows enterprise deployment, where you may have multiple sites spread around the city, state, the entire country, or internationally. Sofia secures, segregates, and allows you to maintain the data for each site individually.