10 Extensions - R499.00
Vibe cost for 10 simultaneous calls - R175.00
Call recording for 10 extensions - R400.00
Call storage- R125.00
Total R1199.00 (pretty close to my original estimate--not based on your rates)
The above is only the monthly cost, the OP still needs to buy the Vibe enabled router, pay for the ADSL install and the normal voice line rental, the IP phones and then decide if he wants to be penalized for going pre-paid, by getting charged premium blended rates and per minute.