If you are a furniture sales rep....

Don't just 'drop by' and expect to give an impromptu sales presentation for your product line. Its unprofessional for you to assume you can do that without an appointment, and you interrupt the work flow in the store. That gives you two out of three strikes before you even open your briefcase. Older reps know this - the newer, young ones don't. If you want to stop by and look and see what the store looks like - that's fine. Do that, hand over a business card and ask "May I call you to set up an appointment to show you my line later on this month?" That's how the pros do it.