There are scammers, preying on people with wanted ads. They find your ad, then find a pic of what you want on Google, then photoshop an index card with their name, date and time, making them look legitimate. When you agree to a price, they want you to friends and family paypal them and boom, they got you.
It happened to me but luckily I had my bank do a stop payment to paypal on the money. I also found this person doing the same thing on forums all over the place. They always join with a "Newbie" post about how they like guns, long range shooting, and learning new things. Then they look for In Search Of or Wanted ads, and the thieving begins. Brilliantly wrong what they're doing... stay vigilant!
They also only text you, no calls. It's from a phone number that when you call it back, is a Google internet number.