Questions in Spiceworks

We were recommend spiceworks for our help service desk.  We understand we can have our office staff all connected with no problem.  However, we wanted if any EE with experience with tool can help us in the following:

• How viable would be to have also some our clients connect to spicework to place ticket-request?

• If ok to have clients connect, any security issue as to a client can have access to our system?

• Can spicework used to assign task to a group of users?

• Finally, can we also include inventory of our tech in the help desk?

Thank you in advance.