Keep in mind that there are those that have CL apps that as soon as something gets posted, it send them an alert. So, chances are that by the time you post something, the seller's already getting calls from those people.
The only true recourse from this kind of thing is if the seller is completely unwilling to ship. Keep in mind, too, that most people would like the money NOW, in CASH and have the pin leave at the same time. They don't want to wait a week, get a "cashier's check" they hope is good, and then have some shipping company hopefully show up in a four hour window that they have to take time off work to make sure they're home for!
Use this argument to keep a local sale local if the seller is saying something like, "There's one guy from the internet who'll give me $XXXX......"