@Blagoje0 I'm sure that was the case. I meant that using the forgetting as a regular trick might backfire at some point.
I especially like your tip with the little greeting note in the guest language. I 'll try that with my next guests this week and see what happens. The one with the key is great too. I'm always around for guests checking out because there is no key drop outside, But I normally tell them upon leaving they were great guests (mine usually all are!) and they'll get a top review.
The notebook one probably works with different accommodations. My guests get a house manual with lots of info. I personally have never liked it much myself when staying somewhere and more or less expected to leave a message in a book, so I don't do the guest book thing, esp. with my guests who are manly very short stays.
Anyway, it sounds like you are very creative! Happy hosting further.