-LRB- CNN -RRB- Craigslist reports about 80 million ads on its site each month, so even if you have n't met a stranger to buy or sell something online, chances are you know someone who has. The overwhelming majority of transactions go smoothly, but the site has a history of being co-opted by criminals on occasion. A couple from Georgia was traveling to a Craigslist transaction last month when they left their suburban Atlanta home in hopes of buying a 1966 Ford Mustang. They did everything right -- they went together, and they told their family they were going to the transaction. Yet the bodies of Elrey Bud Runion, and his wife, June, were found January 26, police said. A South Georgia man has been charged with murder in their deaths. In a separate incident Friday, two men in Georgia met a seller to purchase a dog. The seller drew a gun on them in an attempted robbery, but one of the buyers was carrying a handgun and fatally shot the seller, police said. The investigation is ongoing. The recent incidents should remind those engaged in this type of online commerce that it pays to be vigilant. So what can you do to make sure you do n't fall prey to ne'er - do-wells next time you respond to an online ad ? Philip Holloway is a law enforcement adviser and defense attorney with some tips on things you should remember when buying and selling goods online: 10. Do n't reveal personal