@Abhimanyu Ghoshal - Wise is quite cheap.
They charge a dollar amount fee (for ex $12-15 for $500). That will be shown to you when you withdraw your USD balance.
But you get the exact going forex rate which is the best part. Especially great now because USD INR is at 83+
Also, there is no additional fee to transfer to your bank.
It's been my lowest cost payment gateway yet.