If you have never opened up your home to strangers on a regular basis, you might think of it as a creepy business. Yet millions of people do it.

In 1974, my father and I were met at the Amsterdam train station by a woman carrying a sign that said “Room for rent for night” or something similar, and we stayed with her. That was back before the internet and booking engines.

Of course, the woman charged much less than a hotel. She was glad to pick up some extra change, and my father and I were glad to get a room at a very reasonable price.

We’ve rented out our back room to summer visitors for 10 or more seasons now, but it was not until I discovered the booking engines that we increased our number of new friends fivefold.

If you’ve taught school, you remember the exceptional students. That is, the brilliant ones who became internationally famous or died under mysterious circumstances in Brazil. And until the day you die, you’ll remember the unfortunate ones with some kind of mental disorder who might fly into a rage or simply walk out the door and not stop until they were home five miles away.

The same is true of bed-and-breakfast friends. More than a few come back year after year and stay in touch over the winter months with pictures and notes about the family. Only one or two were completely bonkers.

In my experience as a teacher and a landlord, I would say that one encounters more disturbed students than disturbed B&B friends. Perhaps this is because adults are more adept at concealing their problems than children. I can’t believe it is because only a few ill people travel, because, from what you read and see on TV, they do make up a fair share of the general population.

We’ve been lucky, and have on only one or two occasions out of hundreds found ourselves saddled with someone who would never have been allowed in the door had we known what we were up against. And they were not dangerous – only unusual. A man over 80 can only wonder what a young man could be doing in a closed room for two days with a voluptuous young woman who arrived by taxi with a huge pizza. They emerged only to walk around the house for cigarette breaks. Cigarettes are verboten not only in our rooms but anywhere else on the property.

And then there was a woman who wouldn’t drive on the grass. Because countless cars are either coming or going here, and because trucks hauling white-faced Herefords might at any time lurch through our driveway, we have implemented a very efficient traffic pattern. New friends are carefully guided into their parking places. They park on the lawn next to the door. It facilitates loading and unloading. And because they don’t back up when they leave but simply drive around the house, to date no one has backed into another car or tree.

Hundreds of happy friends have quickly followed the old man who, waving and pointing, directed them to their own secure parking spot. Our literature even mentions it: When you leave, do not back up. Drive around the house and go out the driveway.

I have often joked about people from away who consider driving on grass to be sacrilegious. It takes an inordinate amount of cajoling to convince them that, yes, they can drive on the green part. That’s what grass is for.

But here’s a woman who absolutely refused to drive across our lawn. She had reasons for not doing so. She might hit a bump in the lawn and tear out the bottom of her car. With a great amount of foreboding she finally got her front wheels onto the green carpet, but, like a kid on the edge of a high diving board, it was too much for her. With sweaty hands gripping the wheel, she took a few deep breaths and committed the greatest transgression possible on this farm by backing into the security of a gravel driveway.

There followed several drawn-out discussions between the parking attendant and other occupants of the car. They’d get in the car as if to leave, chew things over and then emerge once again to explain that the driver was from the city and was frightened by grass.

All of the above might sound reasonable and understandable. But every time they’d get out of the car and walk over to me, they’d extend a hand and introduce themselves – as if we’d never met before.

I was trapped in “The Twilight Zone,” and although we’d lost the income for two rooms for two nights, I was relieved when they finally got all four wheels back on the town road.

They even rattled my wife, Marsha, who has nerves of steel. She asked me to stay up with her an extra hour in case they came back.

So I didn’t get to bed until almost 8.

The humble Farmer can be heard Friday nights at 7 on WHPW (97.3 FM) and visited at his website:

www.thehumblefarmer.com/ MainePrivateRadio.html