@Ruben306
Firstly a head's up - when you are replying to someone on these forums it's helpful to tag them with the @ symbol and then their user name - it will usually appear in a drop down bar - then thy'll get an alert.
I was in exactly the same position as you when I started hosting and I had similar experiences adn got similar advice re this from @Paul1255
I had "self check in" selected as my option and a line saying I would be there in person if I COULD. I naively believed being there in person was the more desirable, attractive option to guests. I learned VERY quickly this was not the case. First of all guests don't read and most of them hadn't seen the sentence that I would try to be there.
There is a certain type of guest who very definitely does not want to interact. There is also a certain type of guest who sees self check in, no security device, remote host and begins to make plans.... These are not the sort of guests I feel comfortable having in my place.
On the basis of @Paul1255 's advice I changed my listing from "self check in" to "I would be there" and added a sentence saying easy self check in was available on the rare occasions I couldnt' be there. I clarify which way it is going to be after the booking has been made depending on my commitments.
Since I did that my type of guest has on the whole been utterly different. Previously they were almost sullen at check in, now I get a much friendlier more "airbnb" style of guest.
the only downside is that my listing now can't show on the work collection because I don't have self check in selected ( another restriction of the platfrom - it can't conceive you can offer BOTH it's only one or the other)
The reaction of your guest would really be ringing alarm bells for me personally - I'd be wondering what they were up to. I personally would be cancelling - trust your gut - if it seems off, it almost certainly is. You dont' need the anxiety you'll have leading up the booking as well as during the booking wondering what they are up to. Plus it doesn't hurt this type of person to discover they don't hold all the cards - it might be a good wake up call for this guest to find his booking cancelled.
If you dont' already, Id suggest getting a monitoring device ( be absolutely sure you disclose it in the "other things to note" section of your house rules).
The combination of "host will greet in person" and "security recording devices present" go a long way to eliminating those guest who deliberately search for places where they can take advantage.
Just my thoughts