Rule #1. If it sounds to good to be true it probably is… RUN.
Rule #2. Don’t give your address out unless you have the other persons email address and phone number.
Rule#3. There are tons of scams. If you are selling something and you accept a fake check or money order you are going to be pretty upset. Require CASH if under a couple hundred dollars.
Rule #4. Meet in an area you are familiar with and take someone with you. You may even want to do some Google searches on the phone number someone gives you, the address they give you and the name of the person. You just never know what may come up.
Rule #5. If you are selling something that is high priced you may want to meet at a local bank. Get the money in the bank, deposit the cash in the bank and then give the product.
Rule #6. Give a bill of sale and your terms. If no warranty put that. Be specific as to the terms so no misunderstandings exist at a later date.
Rule #7. Think! Don’t be so excited about seeing something or selling something that you miss all the signs that lead to you getting yourself in a weird position.
Be smart and you will do just fine.