There are lots of considerations so this is not an easy question to answer as I have yet to go brushless but to give you an idea ...

E flite Park 480 BL outrunner brushless $69.99

E flite ESC 20A $41.99

Hitec micro HS 55 13.99 ea x 2 = $28

Hitec electron rec 6 ch $54.99

total (not including radio tx and crystal) $195....



Battery you could use the stock Nimh to save $$ otherise tack on another $50 for a an E Flite 1200 3 cell lipo

Not cheap but if you plan on doing some serious flying it's not a bad way to go to get away from brushed motors. Even at $10.00 a pop if you fly a lot you'll be changing them fairly regularly and that will add up....

I'm sure there are lots of options for cheaper brushless upgrades but remember you get what you pay for.

Cheers