I did a few wrong houses when I worked for AlmostGreen. And a few times when I worked for myself.
Why is it so difficult for people to put a number on their house? Its the law, you know.
Did you ever have the problem when there were 4 mailboxes with numbers, and four houses on four long driveways with no numbers?
And chances are its out in the country--ten mile drive if I have to go back. So take your best guess or ...call at night, and just go back the next time you are close to the location?