Hmmm, that's kind of trange. Are you considering breeding or...?? I understand the whole modeling them off as an excuse to keep them and all but keep in mind, some BPs will shy away from that kind of exposure. Will the modelling site be profit driven?
In terms of upkeep, you're looking at probably fairly expensive, as you'll want lot of snakes, so that your photograph subjects dont get repetitive. Feed, caging, substrate, possible vets bills can all really add up. You'll probably want to consider raising colony of rats to maintain your growing number of models. Could get pricey.
Just a few things that went throguh my mind whilst reading your post.
Good luck.