We have 29 residential yards that we mow. For these lawns, at the end of every month, we drive to all the houses with the invoices. We go to the door and ring the bell. If they are not home, then we drop the bill in the mailbox with a self addressed envelope inside, but if they are home we hand them the invoice (still with the self adressed envelope inside). I have always thought that we should do this since we are on first name basis' with our customers and know a lot of them outside of cutting grass. Today, my brother asked me if I thought this was unprofessional. I thought to myself, and said that if we were on a larger scale of business with say, 80-100 yards, then we would probably send the bills to them through the mail (since we wouldn't have time to go door to door). For the amount of yards that we have, I think that what we are doing isn't unprofessional at all. What do you guys think? Should we continue to bring them the invoices personally ringing the doorbells, or should we just send them through the mail? Thanks for the help.