Thanks for replying. I did try an alternative to searching for data. As described in the OP, I saved the appointments under the appropriate Business (Business.Appointments (list)). My problem lies in how to only show Slots in the dropdown that satisfy the condition that they don’t show up in any of the Business.Appointments.Slot (ie, each Business has an Appointment list, and each Appointment has a time Slot associated with it - ie, how do I add a condition that says “This Slot is not the same as the Slot in any of the Appointments associated with the Business associated with the current marker selected on the map?”).