If you already have Interent connectivity at your main office location, you will only need 1 LAN-Cell deployed at the remote location.  Your cellular network operator will act as an Internet Service Provider (ISP) and the LAN-Cell will be "on the Internet" via the cellular network.  You can access your remote location using your existing Interent connection at the main office.  A second LAN-Cell could be used as your main Internet connection (wired or cellular) at the main location if there is no other Internet connection available.