I've been kicking around the idea of doing the same as you. I have a buddy who built one this last year, and we were talking about it. After you figure in all the "labor hours" of building one, I don't know if you are that far ahead. I know he's got over 125hrs into his.
You figure what 125-150hrs are worth to a guy, I'm not sure if I would go through the headache of building one, other than being able to say I did!
On a side note, nice house!