R.S.
When my daughter was 7 she rode the bus home and one day decided to get off at a different stop. She wanted to visit family that lived near there. So, she got off at the wrong stop (the busdriver didn't say a word), walked to the family member's house, went in the unlocked back door, got a snack, turned on cartoons and hung out for a while. I was outside when the bus stopped at my house and she wasn't there. The driver couldn't remember where she got off. I called 911, was histarically crying, thinking the worst, neighbors, police, everyone was looking for her. It was very nightmarish. She left to walk home when Scooby was over and I found her walking down the street.
So, I think if you do it, the older buddy neighbor idea would be a really good idea. You also have to consider the child's personality. My son when never do such a thing. Good luck.