Its usually cheaper to buy all at one time. I would not recommend buying used electronics, it can be fatal to your plane. You never know what you'll get. The price of some of the packages out there make it actually cheaper to buy new. I bought a cheap radio package awhile back just for the receiver and servos, gave the transmitter away. It was cheaper than receiver and battery alone! The 9c from futaba is a great radio, although it might be a little overwhelming for someone new. Lots of bells and whistles. Just gets someone at your local club to help with setup and keep it simple.