There is no RV, truck, or car.  They make up a sob story about how it belonged to some recently deceased relative.  They want to sell it quick and the price is low.  Sometimes they claim the shipping is already paid for because someone else backed out of the deal.  Then you are supposed to send them the money by untraceable means, or use ebay motors ( the e mails you get will be fake)  You are then out the money.  Common scam running on Craigslist.  Always, always only do business in person at a secure location (many PD's will allow you to use their premises).