Done by gtfmachida - 30,000 Yen.
Done by jyuis51 - 29,000 Yen.
Done by zgmf_xg - 27,000 Yen.
Plus many others which are priced between 8,000 and 15,000 Yen.
Most of the work shown, including the top three on the list shown above featured mainly heavy paint work, which minimum modification to the model itself. I believe this goes to shown how well the mechanism of MG Exia is, and not much modification is needed to improve on anything. It would be very interesting to see how folks modify it in future BAKUC and other Gunpla competition. ^^
All images from Yahoo! Japan Auction.