Why is there discrepancy in member totals per plan?

If your network offers multiple concurrent user memberships (meaning that a user may have an individual and a company membership at the same time), it is possible to see varying member counts depending on where you are looking.

In the admin panel, some users display their company plan instead of their individual plan and visa-versa. Why?

In your admin panel under Manage > People, if a user has more than one active membership plan, the displayed membership label is the membership with the latest expiry date.

When inviting to an event based on membership type, I get different counts than those displayed in the admin panel or reports. Why?

The admin panel displays membership type based on latest expiry. In contrast, event registration looks at all active memberships to generate its counts. Therefore, if you are inviting users to an event based on membership plan type, the membership counts may seem inflated. This is because for the users that have concurrent company and individual plans, they will contribute to both membership type counts in the invitation window. For example, if there is one user with two active plans, in the event invitation-by-plan window there will be a count of 1 beside both plans which may seem to indicate two users. However, this is simply the one user contributing 1 to both counts.

When making a report based on membership plan type, the user counts may seem lower than they should be. When using reports, if a user has more than one active membership plan, the plan expiring latest is the one that will be displayed. Thus, any given user will only show up on one list when using a filter for Membership Plan.