Cheap trainer
The cheapest trainer on the market also happens to be the best!! But you will have to build it yourself. The good news is it is so easy to build and even easier to install the radio and engine! So easy in fact that you can probably have it in the air as fast as many ARFs!!
The Balsa USA Stick .40! About $50.00 last time I looked. Add a cheap .25 - .40 and a radio and you should be in the air for less than $250.00! Find a used radio or engine on RCU and you could do it for under $200.00.
How's that for cheap?