how to reprogramme keyfobs on to gardtec ace 800 alarm?

hi. does any body know the easiest way to reprogramme keyfobs on to gardtec ace alarm.. the alarm is 5/6 years old dont know the user code or master code, have lost the manual. i email company that fitted alarm they said they wont give me information and its going to cost £100/£150 as the whole system has to be "rebooted and reprogramme" i was messing about with alarm and types in 000 in user code and it said error so afraid of messing up the system. any help ,advice is appreciated..


being a single mum i cant afford £100/£150 to get it reprogramme

thanks