When a user enters an address that is not listed in the database, they will still be able to enter the address details manually. AddressFinder will still return addresses that are the closest matches to the address that has been entered, but if the correct address is not listed the user can complete the 'Address Line 1' entry, and then move on to 'Address Line 2, Suburb, Post Code etc'. Therefore you will not lose customers because their address is not available for selection from the drop down menu.