Dotsie, the "Nigerian Scheme" permeates alot of things having to do
with money. At one time I subbed as relay operator for deaf
people and they pretended to be deaf and order big ticket items
with stolen credit cards!

Back to your son, he CAN list the camera again, but he must stick
to the "only U.S. bidders." He can reject the bid. Also, as long
as the money is not deposited in Paypal, he loses nothing as long as
the camera is not shipped.
This link has a ton of valuable information for sellers.....
http://pages.ebay.com/sitemap.html

My husband said that the schemers are usually attracted to
expensive camera equipment etc, as it is easy for them
to turn it around and sell for profit.

As for reposting, it is commonly done due to reasons such as
no one was interested in the item the first go-around. It could
be that the original bid price was too high, too. Or just the wrong
timing.
Or reposting can be due to the final bidder not fulfilling
his or her part.

Most buyers and sellers will have no problem with eBay as long
as they follow the common-sense rules. And it is an immense help
and empowering to read all of eBay's helpful links for sellers
and buyers.

Let us know what happens..........

Cindy