I have a 14 year old but he'll be 15 next month so I know where you're coming from! Mine is into baseball too and while i can't say we all the same problems, we do have some of them. He does push the limits and he really doesn't seem to appreciate things and thinks money is no object. I need a new $300 bat, so what's the big deal? No advice for you....
Sorry, but don't take it too personally, he will grow out of it!