HI I am Samco trader. I share one my experience. I pledge my liquid bees etf and gets collateral of Rs. 200000/. Please not that pledgeing of liquid bees etf is equivalent to cash so no 50:50 ratio required as per SEBI rules. Samco is charging interest on margin used for Future buy or sell even within collateral value Rs. 200000/-. While other brokers like Zerodha and Upstox is not charged for the same.