Dont matter what is your budget if you consider these points during buying bike, you will surely satisfy with your bike:
1. First You should make sure about that for what particular work, you need bike .
2. If you are a regular user of bike for long rides, You should consider about first: its engine quality, average fuel capacity and its reliability.
3. If you use bike for heavy loads than you should consider about its HP power and engine reliability .
Company Service center and availability of its parts .
Your comfort, height and physic( heavy bike like bullets:you need to have good physic to control bike)
Fuel Tank capacity.
Acceleration and top speed.
Take a test ride. Just dont follow what people say, first you should take experience and then decide.
Reviews of people who are using the bike for long time or have some experience with the bike.
Last but not least pillion comfort, Cause when you are with your girlfriend, you will not want to make her discomfort.:)
Hope it will help
Enjoy Your Ride