Because they saw his face.
One relatively safe way to do a cash transaction is to have the guy meet you at your bank. Go inside, where he knows he will be visible on bank security cameras, take out the money, have him hand over the property in front of witnesses and bank cameras, hand the money over, it's done. You might even be able to have the bill of sale notarized there.
And as others have noted, have a good friend in the parking lot as armed backup and overwatch.
have the guy meet you at your bank.
One relatively safe way to do a cash transaction is to have the guy meet you at your bank. Go inside, where he knows he will be visible on bank security cameras, take out the money, have him hand over the property in front of witnesses and bank cameras, hand the money over, it’s done. You might even be able to have the bill of sale notarized there.
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I have sold two vehicles and bought one. Always call my credit union ahead of time. Meet in lobby, look over vehicle there, Test drive it in the lot do up the sale in the lobby, often with the manager’s help.