What an incredible work, congratulations to you and Tony on a job well done! As an HMR fan, I'd love to have one.
Around $200 is the most I'd be willing to spend on a professionally built version, but like Mommar said, I don't think that price is practical.
As for other schemes, the only other one I'd be interested in is a Roy scheme. And a downpayment sounds perfectly reasonable considering the labor involved.