[Serusers] Help with SER & 10 users

Hello All, I am new SER and trying to get information on how it work. Before i sign up for this list, i was regular lucker of the mailing list. I know this subject has been discussed lot of times but i find the proper answer for this. I guess some will be able to help me with what i am trying to do. I am planning to have about 10 users connected to SER server and then they should be able to call any number they wish. I mean to outside world. Instead of having 10 different account for this purpose, i would like to have one account and have them use the same account to make outbound calls. I don't like to give them the login/password to the main account. Can i have a SIP provider (like voicepulse) register to my SER server and then all the 10 users connect to outbound calls through SER? Please help me to get this working. TIA