Cisco SPA9000 VOIP PBX installation and consulting

Hi, I need someone to give me advice and to install a VOIP telephone system for me. I work together with 4 different people. We are all 4 in 4 different locations. I want that we all can be reached under one phone number. Basic requirements: -One phone number -Extension for each member -Receiving fax -call transfer from one extension to one other -conference calls -voicemail I was thinking of a Cisco SPA9000 as PBX and have IP phones in the 4 different locations. I can have a fixed ip number where the PBX would be installed. But I´m not sure if that would really work. Don´t I need to create a VPN between the 4 locations ? Also I would need to use 2 SIP accounts. One for incoming calls and one for all outgoing calls as my SIP provider for the incoming calls does not provide the possibility to make international calls. I would prefer a CISCO PBX to a software PBX as I believe that it would be more reliable. I would let you connect to a machine here over [login to view URL] to make the installation and setup remotely. ## Deliverables you should setup the PBX, make eventual network changes and setup the ip phones.