The RC helicopter and airplane hobby can be a money black hole.
The nitro (liquid fueled) types are the best as far as performance go, but are the largest and most expensive. The battery powered ones can be had quite cheap but flight time and performance aren't as good as the nitros.
Oh, and the first RC helicopter you fly will crash, possible several times before you can exhaust a fuel tank or battery. So if you do want to learn, don't start with the most expensive aircraft available.