I am developing a very small MS Access application that has four basic tables that enable users to track Customers, Assets, Crime Statistics and Vehicle Information. At first the app will only be used in one office but eventually half a dozen or so users will want to use the app. All of them will want to keep their Customer and Asset tables confidential. The Crime Stats table, though not confidential, need not be shared. However it will be to their mutual advantage to share the Vehicle Information table so that when one user updates the data the information on that vehicle will be available to all other users.
Am I wise to set up this sharing by using a VPN with all offices (separated by hundreds if not thousands of miles) reading and feeding the data from a central table, or should I set up regular automatic email updates of updated records, or some other mechanism?