Hall County will begin mailing mobile home tax bills today, a week earlier than in previous years, to avoid a 3-cent postage increase set to take effect Sunday. The price of a stamp will increase to 49 cents, generating an estimated $2 billion in additional revenue for the U.S. Postal Service. Mobile home owners have until May 1 to pay their annual property taxes, and will be issued a decal that must be displayed on their properties indicating they are in compliance.