I guess the people in my area are very ffriendly folks. I pays to be friendly and get right to the point, being respectful of thier time. Im a musical instrument repairman and I get annoyed at people who tell me thier life story as if I have all day to spend. Im also very helpful to people if they are to the point and respectful often giving away scrap horns for art projects etc.
One other tip : visit them at a time when they are not at thier busiest, even asking them when that might be and or setting up an appointment. If you make friends with this person, they could be a valuable sorce. It doesnt hurt to buy what you can from them too! good luck.