3. Disqualify the Time Wasters
For the Nigerian scammer, turning away the wrong person is probably as important as finding the right one. That's why the scammer doubles down on the poor grammar and outrageous claims--he's just making sure that you and I have absolutely no interest in responding.
Successful businesses prequalify customers in the same way. That's why high-end advertisers often include prices in advertising--such as the Jaguar ad stating that leases start at "only $649 a month." They aren't trying to impress you, but rather to disqualify customers who can't actually afford the car.
Properly targeted advertising limits time and frustration of people who aren't appropriate for your product or service--and keeps your sales team talking only to likely buyers.
This was an article about how the Nigerian email scam is a success - but I pasted this because of the reference to posting your price to eliminate low end buyers.