Another thing to consider is that Yamaha G series is not really designed for advance players who will really put the instrument thru heavy playing. It will simply wear out too fast. The action will not put up with the heavy use, and will become very loose. G's are more for beginners, light playing, and furniture.
The C series is intended for more strenuous use. Hence the price difference. I'd shy away from the little G. If you're a serious, and advance, player, you won't like it for very long.
Just my opinion, based on having to use both series in venues where they get heavy use. The G's don't cut it. And of course I have a steinway, so I'm a little biased! (actually the nicest grand in my area is a Yamaha C6. The big Steinway at the big theatre is not regulated well enough, needs new hammers, but the cheap bastard that manages that theatre won't get it fixed!)