Does a multi user calendar and invoicing software exist?

[iMore Question]

multi user calendar and invoicing softwear

Hello I'm looking for a software that I can put the date time client, participants, p.o number, fee (must be changeable of each participant as fees vary ) into a main calendar.
The names of each person booked trigger info to go to their own personal calendar that they can access online. Participants can access their own personal calendar and add their own personal info ( add booked out) but not change my bookings. Info from all the personal calendars can be grouped to make monthly invoice.
Does something like this exist... Any advise?

Thanks

 

[SwitchBeach]

Re: multi user calendar and invoicing softwear

On what type of device?
What operating system?