nice query,but i feel there are some confusion in your mind reg telecommunication head. we can discuss full business plan in detail.
few details :
Here in india E1(2 Meg link) line is provided by vsnl,which charged approx US$ 54,000 per annum.
There is no need for ISDN line for setting up call center.
working invironment is :
24/7/365 for call center setup.
and effeciency can be calculated
once the details of your requirment known and can be calcualted with help of erlang calculator.
same thing is true with the salary and other detail including churn rate, i mean to say according to you business need.
there is some basic difference of working environment between singapore , china and india. so you can’t compare that simply.
hope i have given satisfactory answer to some of your query.
we promote call centers in india, so in case you need professional help/services i will be glad to do so.