I propose a temporary ban of a couple of days after an individual gets tagged with a certain amount of missed meetings. If this continues perm ban.
Also I see we have under portfolio number of sales it should also include number of negative reports on the person such as missed meetings.
I would hope these features would curve people's attitudes.
If you don't want to deal with flakes, use eBay. Otherwise, just deal with it. As Goblin has laboriously noted, people are different.
Unless there is some legal/contractual obligation/consequence, people will do what they do. It may sound stupid, but that is reality. Even if TruYou becomes a requirement for all users, there will be inconsierate flakes that don't care about getting banned,etc. Currently, it is too easy to make additional accounts, so bannning users will not even make a small dent to the problem. If banning is a partial solution, they should start banning MAC addresses instead.
On a positive note, OfferUP is slowly emulating eBay with rolling-out the shipping/PAYMENT system, so maybe the payment system will be the "secret sauce" to discouraging flakes.
Offer a realistic solution to the problem, rather than just stating the obvious issue.