If you choose 'India Direct Mail' For Banggood and 'Priority Line' for Gearbest then there is No Customs Duty need to be paid - This is 100% tested method by many people from India. All Product doesn't have such shipping method (Example: All Phones, Tablets, Laptops don't come under this shipping method)...This shipping method only available for China Wearhouse. HongKong and other European Wearhouse don't have this shipping option.
Sorry I didn't use this method - Using Paypal route is much easier and safer, Paypal will work with any VISA certified card - Yes Debit card too, You can register and activate your PayPal A/C if that card is not in your name too.