To setup OrgChartHub within your Hubspot account you need Sales administrator access. Once a user with sales administrator access has setup OrgChartHub then all of your Hubspot users will have access.
Yes, OrgChartHub is built for teams, any hubspot user from within your account can view and edit the orgcharts you have created.
No, OrgChartHub does not store HubSpot contact data from your account. We use the Hubspot API to present the contacts and OrgCharts back to you and only store chart-related metadata on our servers. You can disconnect OrgChartHub at any time.
When you first setup OrgChartHub it will position itself at the bottom of your side panel in the accounts page, however you can drag higher up the page.
OrgChartHub remains within it's own API limits, and so does not impact the amount of API calls you can make for yourself or with other connected applications.