In contrib/customer_otherip directory you can find equivalent of "Customer account" module, which does not authorize user basing on his IP address, but requires login. Authentication can be performed basing on user's PIN number and phone - or alternatively ID or contact number - as username, see balanceview.php and authentication.inc files).
Script shows user his balance and contact information, and, with help of contrib/formularz_przelewu_wplaty gives user a possibility to print money order for his debts.
It also allows aquiring and printing invoices by customers
All installation is limited to setup of sys_dir option in [directories] section of lms.ini file and linking img/ with UI icons.