RE: Found a used nexstar setup
A couple of things to check....
Have him charge the batteries in both the transmitter and receiver and turn them both on.
Then see if the receiver works by moving the sticks on the transmitter back and forth....You should see the control surfaces on the plane go back and forth as you move the sticks on the transmitter.
You will also want to check to see that the main wheels are tightly snapped together.
Then start the engine and throttle up and listen for the engine to transition smoothly to full power.
About the AFS or auto flight thing....I wouldn't worry about it. You will want to turn that off when you start flying...it's crap and won't help you learn to fly.
Make sure you get the simulator software and transmitter connector so you can practice on your computer. It's a great way to practice flying without risking your bird.
I learned on a Nexstar and really enjoyed flying the plane....so if you could get a good deal on one - get it....you will enjoy it.
PM me if you need more info or help with the plane.
Scott