Which bike i will buy?in 125 cc range as better performance ,fuel efficiency and re sell value.

Well, Discover is a good option. Not sure if its coming in 125cc. But 115cc is doing great.either go for this one or upgrade a little and go for pulsar 135. Re-sale value toh boss, bullet ke alawa kisi mein nahi milegi.

Hi, both Honda Activa and Suzuki Access are good reliable scooters. The new Activa has reliable 109 cc, Air-cooled, 4-stroke, single cylinder, OHC engine with 8 hp @ 7500 rpm of power and has 9 Nm @ 5500 rpm of torque with overall built quality and has very good resale value.
The Suzuki Access has 125cc reliable engine with 8.5 hp @ 7000 rpm of power and has 9.8 Nm @ 5000 rpm of torque. Honda Activa has mileage of around 42 to 48 kmpl where as Suzuki Access has 40 to 45 kmpl depending upon the riding conditions and style. The Suzuki Access is much better to ride because it has telescopic front suspension.

So in my personal opinion its better to go for Honda Aviator, because it is an up graded version of Honda Activa. Aviator is having the same engine, power, mileage of Activa. The Aviator has telescopic front suspension for better comfort while in riding and handling and has additional features than Activa.
So test drive the Honda Aviator and feel the difference.