Have you guys been able to negotiate CPA terms with media buys before? I doubt an ad network will agree to it, but I'm going to try to negotiate CPA terms doing a direct buy with a website.
Ad networks will try to help you make money because they want to keep you as an advertiser. The only thing I've been able to do with an ad network is tell them my CPA goal and when I very first started with media buying I had a great manager that helped me reach my goal in 10 days...I then was doubling the money I spent everyday. I started using Adblade. As far as website owners...never tried doing that, just too much work for me to hassle with them and even bother. I like to get now traffic even if the ROI is most likely lower, I'd rather make $1k-$5k+ everyday instead of one month. Good luck and let me know how it goes! Best, Ryan.