Actually, that's not such a rare thing if you live in the country like I do. There are lots of people that live just out of town that get their mail delivered to mailboxes more than a half mile from their house. We used to have a friend (before he passed away) that had some of his mail delivered to a mail box on some property that he owned about 5 miles from town. It was just a mailbox on the side of a dirt road and he asked that we check it every few days since we were out that way anyway (we had cattle on his land at that time). Anyway, every time I would go for a ride, I would go check his mail and our cattle to save 10 miles of burned gas from the truck. Occasionally, he would have some letters or a magazine that I would then get to carry back to town.
And I know a real test to see how good your horse is at opening gates. A panel gate is a simple thing. When you can open and close a barbed wire gate without ever getting off your horse, then he's pretty darn good.