The problem with the rupee ocarina is that it's really tiny! Everyone always tells me my hands are small, but it's still kind of weird holding it. It's also only like six holes compared to the Ocarina of Time's 12, so to get some of the notes out you have to cover half a hole. It just feels really weird to me, but it is a cute little instrument. Where did you buy yours from? The issue some people have with OoT replicas is that the game actually didn't get the ocarina shape right (no flute or flute family instrument can be held like that lol), so they all look backwards, but it's not that big of a deal IMO. I'd like to practice some more and get the Fairy Ocarina from them sometime, and maybe work my way up to the more complex ones.
Ooh wow, that's really impressive! My dad likes to build stuff too (he's not a carpenter though), but I've never really been interested in building stuff on my own, for the most part. Have you ever thought about building stuff as a type of job?