Sorry, edited to say: posted on wrong thread but can't seem to cut and paste it to the right thread. Just ignore.
I have an air BnB which is a sort of annexe to my own house. I can choose to rent it out when I am there, or not there, but I never rent it out when I am not there and this sort of thing is the reason why. I would not want some sweaty six foot bloke sleeping on my sofa, thanks. Especially not without a full and proper set of bedding. And a single bed in a holiday let may not be of the quality to withstand the weight of two shagging adults. The hot water capacity may struggle with extra people showering as well.
I make it clear on the listing that we live on site, so even if we choose to go away for a few days during guests' stays, they always book in the knowledge that we will see whatever is going on. It works because it puts off the people who might want to take the piss.
I know of people who have booked nices houses with pools sleeping 4 or 6 while the rest of their family or friends are in a cheap place with no nice facilities down the road. Then they turn up at the nice villa every day to use the pool and the wifi and the bbq, the garden furniture, the games room, the loos and the sunbeds then bugger off again at bedtime. So the house may only be sleeping 4 or 6, but everything else is taking a battering with 10 or 12 people in it.
Also people think if the host isn't there, they can book and pay for a place sleeping 4 or 6 people, then turn up with a load of blow up air beds and an extra four kids in tow. They don't see the harm, but honestly the difference to the wear and tear on your place, your furnishings and your pool etc is huge.