I haven't used OTC service like Zebpay much but have been tracking the prices on Zebpay for the past couple of days.
There seems to be no logic in the spread (difference between buy and sell price)
Their Buy prices seem to be linked to the Coindesk BPI
www.coindesk.com/price with a considerable markup.
Can someone explain how the Sell prices or spread is managed on Zebpay
Below are the two graphs displaying buy and sell rates for the past 12 hrs.
Buy rate goes North and South, Sell rate remains almost constant
Buy rate remain constant, Sell rate goes South.