Date Restricted User Group Access

[vistaroyale]

In our community, we have a lot of renters, particularly in the season (winter months here in Florida.) Upon occupancy, we would like to permit access with more rights than a guest, but fewer than those for owners. I've created a user group "Renters" for them.

Looking for a way to move them from guest to renter and then back again based on the start and end dates of their lease? I didn't see any way to create a user profile field that can be a date format.

All registrations on our forum will require approval with the information being reviewed by staff before any account is activated. We would like to get them set up as soon as the association approves their request for occupancy by entering their information, activating them as a guest, and then notifying them that their account is active as a Guest until they arrive on (include the start date) when the account will be upgraded to Renter status until (include the end date).

Since the Renters group can easily include well over 1,000 people during any given season, any suggestions (free subscriptions, promotions, etc.) would be greatly appreciated.