@Leonardo570 There is no reason to let a prospective guest pre-view your place, and it isn't advisable. More often than not, the reason the guest wants to do this is exactly because they want to try to convince you to let them book off-platform. There are also scammers and thieves who want to do this to scope out your place and what's in it, and come back to rob you later. A guest should be able to determine if they want to book your place by looking at your photos, reading your listing description, and asking you any further questions they may have.
Guests don't "require" a previewing- if they are concerned about making sure it's what they want because they are looking for a long-term booking, you can suggest that they book for a night or two and then decide if they want to book for longer.
And I've read posts here from hosts who said they let people preview the place a few times, and would never do it again- it was just a waste of their time- they spent half an hour showing the people around, after waiting for them 20 minutes past the agreed meeting time, and they never booked anyway.