Change Privacy Settings for a specific blog in Multi site when upgrading to a pro site level

Hey! I need to limit the access to the admin dashboard to my users depending on their pro site level, if they have a pro subscription they will have full access to the WordPress back-end panel, however if they are in another "Simpler" level, everyone (including logged out users) will have access but only to the front-end, as well as if they have a free account which only the "site creator" can access the site ( again, only front-end, not back-end )

How can I achieve that? Hooks, custom code, extra plugins, etc?