I think you need help to value the guitar. The problem is that they are literally priceless to the people who have them, in that they won't sell them but they are not a 'name' guitar so there is no real market to compare them.

If you can find someone who plays and you can trust, get them to play a few Martins and other quality guitars and note the prices, then try the Haruo. I suspect you'll find it's a bargain.

Naemonson is right, I don't think there is any other significant information about them that isn't included in this thread. Good luck, I hope you can buy it and you get as much pleasure from it as I have from mine.