RFID Cards based on prepaid water kiosk/ATM

Hello freelancers sorry i need to develop a prepaid water kiosk/ATM by using RFID cards, the system should include rfid reader, water flow rate sensor, keypad, solenoid valve, one admin master rfid card, 400 users rfid cards, the system should work like this.... first all rfid cards should be added by admin by using rfid master card, also the admin should be the one who is responsible to add balance to the user rfid card if her/his card balance is low. the user should first scan the can the card to the system then after that the system will check if the card is available in the eeprom/sd card database, if is available then the system will check the available balance of that card if there is enough balance then the system should activate the solenoid valve then water will start to flow to the water container and the scan should not be removed from the reader during that process then when the user will remove her/his card from the rfid reader the the solenoid valve should be deactivated then the balance will be deducted according to the amount of water he/she get.