Hi Kaushik,
Since I’ve been trying to do the same in Bangalore, I can tell you that a 50-seater could cost you about Rs1.5 crore plus infrastructural expenses(viz. rent, cubicle equipment, computers, etc).
If you have an inbound account, you can earn around $12/hr/agent. Out of this, your expenses can go upto 80%.But to get an inbound account, your company should have good contacts or proven track record.
If you have an outbound account(which almost any startup company can get), you might earn about $80/sale(varies from client to client) on a product worth $200-$400.
This looks like a lot of information, but I haven’t elaborated. If you need to know more, feel free to get in touch.