I direct commercials for a living. My filmmaking podcast "Respect The Process" is free on iTunes. I teach the successful Commercial Directing Bootcamp.
Gumroad was very profitable for my docu "I Am Road Comic" back when this thread started, but now VHX.tv seems better. Vimeo owns it. Great support in matter of hours, even on weekends.
I chose a 2K DCP off a ProRes 444 master of the film, because the story carries the film and it looks amazing.
Sony AX33 is $700 new, so you can get one or under $500. I've sold two documentaries to Netflix, iTunes, Hulu and Showtime shot on lesser camera. For "I Am Battle Comic", I took the AX33 to Afghanistan and Kuwait, shot NOT 2K but 1080, and had a great colorist. Professional mix as well. Hit me up and I'll share workflow. Hits theaters April 2017.
Love Jen McGowan's take. I actually preach "putting yourself in a box" at my Commercial Directing Bootcamp. It's where you learn the biz & process of what a professional director of commercials does. Note that when you go off to do your feature, you're basically exiting the ad world. When you return, you start over.