How much would you budget?

I don't know if this will actually happen, but if it does I would be working with a very helpful coach/trainer, who has, and still is, helping me through Tango's issues. Anyway, starting in the winter I would like to pick up a project pony, a greenie of sorts to put miles on, a few show miles, and basically 'turn around' to sell. The horse market over here is decent, but if you buy at the beginning of winter you'd be surprised at what you'll find for cheap- but how much should I budget for the initial cost of the horse, and the initial vet check, do you think? What, in your opinion, would a pony of that sort go for?

What I'm looking for would be a pony to get to be kid safe, between 13 and 14.2 hands, no necessary show miles, green broke, sound to jump, etc.
I've already budgetted the cost of the extra feed, blankets, have the vet money set aside, farrier, teeth, etc. But I've never spent my own money on the initial cost, and as much as it could harshly fail, it'd be interesting to put it into perspective, if it's even possible to make money in this industry. I would, one day, like to be a trainer- and for now I'll settle for working with and learning from trainers in my area.

Anyway, I got kinda off topic, haha!
Now! I don't want to hear "that's a dumb idea!" if you don't agree, make sure your comments are constructive, and we'll all take it better, I'm interested in hearing tips aswell.