RE: Price of RC training ?
Formal courses and schools are few and far between. I think I've heard of two.
Of course, here in the US, there are clubs all over, and most have instructors who wouldn't dream of taking money for helping you learn. At my club, two of us spend a lot of time teaching new students. One of us wears a T-shirt that proclaims "Will teach RC for beer". I've never seen him accept a beer for training, though.
Will you be wanting to learn at a location in Croatia? If so, and you can't find an instructor, there are lots of good ideas for self-learning, and the choice of equipment is important.
Let us know if we can help with that.
Good luck,
Dave Olson