Welcome to the hobby (almost).
the diferance in price between a 3 and 4 chanel plane is probably a few $ as they probably both use a 4 chanel or more radio gear, but a nice 3 channel plane can be just as much fun

my advise is find a local club (the nearest one to you i know of is in the UAE) keep WELL away from radio gear on ebay unless it's realy, realy cheap.

Buy a 40 size plane and engine of bigger.

i'm not sure what material resources are like over there but have a look at the scratch build and SPAD forums here on RCU.

good luck