What I like to do is buy media on websites on a performance/cpa basis at first for about 2 weeks just to test if their traffic is quality, and then switch over to a flat rate, cpm or cpc basis if the website owner prefers that. That way I'm not spending any money upfront at first on traffic that could be low quality.
So basically what they don't allow, is the method of payment I choose to use with the website owner.
Whether I do media buys on a flat rate, cpm, cpc, or cpa basis, that's just the payment arrangement between me and the website owner, and I don't see why the network should interfere with that since it doesn't affect the quality of the leads on the cpa network's end. My banners stay on the same spot, on the same targeted websites. Nothing changes whether I pay the website owner upfront, or out of my profits (which they don't allow)
Maybe I'm missing something.
Anyways, are there any cpa networks out there that allow to do media buys with their offers on a cpa basis? At least on a trial basis?