for the planes, have you conisdered a glider of some form? a small one might not have trouble with the wind and fly in a smaller area.

with the heli i dont know, but i will ask around with our heli guys at the field tuesday.....maybe a bigger motor of some variety?(might take a little custimization


you might also look into building a very small S.P.A.D. , go over to spadtothebone.com. there very cheap and easy to make, and a very small electric one might just be what you were needing. if you need help getting materials to mexico, let someone on here now. i for one would gladly ship things to you, and im shure other would to. good luck and dont give up