Access VBA Macro for Database Triggers -- 4

I need someone to create triggers in Access 2010 that will limit what the data can enter. For instance, there will be two rooms. The price of room 2 must be higher than the price of any room 1 (not the total, but the highest price of any room 1). Also, I need a trigger that gives an error when the user attempts to book a room from the same hotel within the conflicting dates with an existing room. The guest cannot make 2 bookings with overlapping dates. You can use VBA. I will pay you $15. Thank you.