@Jean5108 I don't think it sounds like a scam, just clueless, self-absorbed people who somehow expect you to boot someone else out so they can stay, or something like that. If it's just an Inquiry message, all you have to do is message back saying something like "As you can see from my calendar, your preferred dates are unavailable." Or maybe "You really want to stay tonight? I really want a Porsche." :-)) BTW, I'd never accept someone who sent me message like that even if I had availability. If they're that self-absorbed, I'm sure they'd be problem guests.
You can create something like I wrote above in a saved message in case you get more of these, then you don't have to waste time typing responses individually.