Save PPC, itemized bills are the norm. Take a phone bill. It is clearly itemized -- you can see the total matches the sum of the calls plus the taxes, and you can check the individual call records to see if they look OK. Similarly, when you pay the bill at the restaurant, the pre-tip total is the simple sum of the food and drink and taxes. All clear, all auditable.
In contrast, most search engines and comparision engines provide at best daily cost reporting at the ad or URL level along the lines of "this destination URL received 'X' clicks at an average CPC of 'Y', so advertiser owes engine 'X*Y' for that traffic for that day." Many of the feed-based shopping comparision engines don't even provide that much detail.
What if instead the engines provided their advertisers with a log of every click from the last 45 days with these data:
- date and time stamp
- IP address of clicker
- destination url
- valid click flag -- was the advertiser charged for this click, yes or no
- cost of this click
This data would only be available to advertisers, so it shouldn't provide inside information which might aid fraudsters aiming at cheating. Advertisers simply could choose to ignore these reports if they so wished. Careful advertisers (or their agencies) could make sure the total bills match the totals of detailed click-by-click records. More sophisticated advertisers (or their agencies) would dig into these data in depth, matching them against clicks received at the site and checking to make sure there were no unusual patterns.
We itemize our phone bills, our restaurant tabs, our income taxes -- why not PPC clicks?