why dont you try to just get a normal loan first, by normal i mean, but down 5-6 or even 9k down, and just finance the rest. im not SURE this will work because you mostly get paid under the table. but with a credit score like that, they might not even care how much or how you get paid.
just an idea
2006 325i Sparkling Graphite Metallic-Black Leatherette
Navigation-Bmw Assist Automatic-Xenons Carbon Fiber Front Lips-Aluminum Pedals Power/heated Front Seats
5% Tint all around 30% On windshield all the way down