Most of the time people are not home and have keys attached to a locked box on the front door that real estate agents can use to get in the front door, however not all people do this. If you choose not to have the keys on the front door and make an appointment with a real estate agent, please be home and ready to get the door, especially if you were reminded and reconfirmed the appointment earlier in the day. It is rude to confirm the appointment with the real estate agent for later the same day and either not be home or not answer the door when we arrive at the appointed time. We don't appreciate driving to see the home and waiting out in the cold for nothing.
I also think homeowners should either retreat to one room or leave the house when potential buyers come by. It is awkward to discuss the house with DH if the homeowner is right there.
We are both buying and selling, but haven't experienced any rude buyers because we leave the house when there is an appointment. I do agree that buyers should keep their appointments, knock before entering, not touch personal property of the homeowners, not peek in the windows of houses with 'for sale' signs, and refrain from rude remarks about the decor when the homeowners are present.