1)Customers has to automatically notify of any event. --- piece of cake...mail,sms,what you want?
2) New Uder Registration --- sure.
3) User Waitinglist and auto confirmation.
---- sure combine with item 1. will inform automatically too.
4) Admin power to add, edit and delete any event.
---- easiest.
5) admin power to add, edit and delete any user.
--- same as 4.
6) Event registration Auto confirmation.
--- what is the logical to auto comfirmation? with this .sure.
7) Event Scheduling, rescheduling
---- simple with calender...
8) Integration with our existing website which is in ASP.Net
---- no problem.
contact me , we can do it before you pay us.
--- zengzhaopei at hotmail dot com