The thing to ask yourself, and really ask yourself, is "how much will other people's common space habits bug me." A grand villa is big....but it isn't that big when you put eight or twelve people in it. The kitchens remain sort of small, so if you have eight people trying to get breakfast together before getting out the door, it takes some coordination and patience. There are a number of flat surfaces where people will dump their "come back from the park" stuff - is that going to bug you? That many adults means you'll need to organize laundry time.
With my brother in law, I know from 30 years experience that he is a kitchen putterer. It can take him fifteen minutes to make coffee - and his coffee needs to be made to his specifications, he can't just drink the communal pot (you know how Sally in When Harry Met Sally is high maintenance - she has nothing on my brother in law). He gets peevy when people wake him up in the morning before he wants to get up, but his booming voice will carry at 11pm at night when he isn't yet ready to go to sleep. Add in my nephews - who are their father's children - and my sister - who is the great enabler - and I'm not sharing a Grand Villa with them anytime in the near future. I like them, and I enjoy vacationing with them - when its "meet up and spend some time together" and not "trip over the results of their shopping expedition walking through the door." And youth does not temper the maintenance issues with my nephews.
Are they going to get their own dishes done, or with you in the room are you going to become the maid who makes sure there are clean coffee cups in the morning? Are they going to be prompt about moving laundry around - and be willing to answer a communal call for "hey, I'm washing undies - everyone bring theirs out - here's a Sharpie for your initials in the waistband" - or are you going to be looking at loads of four items, sitting in the washer, with a lot of "I don't know whose that is" when its time to move it.
We regularly do an annual big vacation up at a friends house on Lake Superior - its four couples and then some kids. We divide up dinners, we have a pretty negotiated system for beds, people tend to pitch in fairly to keep dishes done and spaces tidy, and we tend to work fairly well together over a long weekend. But its taken fifteen years to get there - and its only a long weekend. Plus we bring in a housekeeper to clean at the end - the point of contention became the end of stay cleaning.