Last May 2013, I have taken 46" Samsung smart TV thro British Airway, I checked in as one of check-in baggage and there was no additional charges. But I have paid duty charges at Bangalore around 8k even through it was one year old used TV. I believe from Aug 2013, the duty charges have gone as high as 35%.

I'm planning to take new 70" TV from USA to India shortly

Is it possible to carry such a big TV even If I'm ready to pay over weight and size ?

I may take multiple flights(domestic and international), is that overweight and size charges have to pay only once during first check in or to pay Domestic as well as international flights separately ?

What will be approximate duty charges at Bangalore for 70" new TV ?