Not Screening Potential Buyers
You want to qualify and screen every potential buyer before you agree to a meeting. Do this over the phone in a conversation, not through texts. This will give you an idea of what this potential buyer is like. Find out who they are and establish a way you can contact them. Then ask how this potential buyer will pay for the vehicle.
Have they obtained financing? Will this be a cash deal? Serious buyers should be able to answer these questions. Finally, before agreeing to meet this person, do an Internet search to verify their identity and address.