@Lauren553 It's not incoherent at all, and I think it's great that you're asking for clarification. To me, as a host, it's something that would be decided on a case by case basis, although I know a lot of hosts simply don't allow anyone who's not a registered guest to be on the property. The problem is that a lot of guests just aren't responsible people- they may have friends over, the friend damages something in the place and then the booking guest doesn't want to accept responsibility for it. Also, there's a vast difference in what different people consider to be a party. A few friends sitting around sharing a bottle of wine, with some soft music playing in the background, and just having good conversation is way different from 20 drunken revelers disturbing the neighbors and making a huge mess. But guests are strangers to hosts, so we can't know what someone plans to do with their friends, whether they're mature and responsible, etc, whether they're telling the truth or trying to make something sound non-threatening, when in fact it could escalate into a bad scene. Therefore many hosts just err on the side of caution, rather than having a nasty surprise.
And it isn't like renting a place on a long term lease- when you actually rent a place, the landlord will normally ask for references- from past landlords, employers, ask for employment history, amybe do a criminal record check. Then they choose a tenant who seems like they'll be a good one. And you often will have a security deposit held by the landlord, perhaps have to pay first and last menth's rent in advance. So it's not at all the same- Airbnb hosts don't have these levels of security.
Also, you need to understand that hosts base their prices on a number of factors- most try to make it affordable, and need to factor in all the things they provide. When you have more people staying, obviously they're going to be using toilet paper, taking hot showers, using the soap and shampoo and creating more laundry as far as bedding and towels go. So that costs the host more- costs that weren't factored into the original reservation.
I know that in many countries, hosts are actually required by the government to have valid ID from all people who are going to be in the home, and no one can be in the house that isn't a registered guest. So in those places, it's not even the host's call- it's a requirement they can get shut down over if they don't follow the rules.
So as far as any of your family or friends coming to visit or stay in a place you book, the best way to handle it is to just message the host, explain the situation, and see if they'd be amenable to it. Since you're not even sure when and if your family members or friends would show up, the host, if they agree, can amend your booking at the point when your family will be there to include them for those days they'll be there and charge accordingly.
As for cleaning- most hosts expect guests to keep the place basically clean and tidy and to clean up their own messes, but the host deals with heavy duty cleaning. On a long term reservation, there is variation in how hosts handle it- some may want to come in once a week to change out sheets and towels, and do a vacuum and general clean-up, some may just have the guests do themselves. Most hosts seem to prefer to handle the laundry themselves, as guests will just throw something in the washer in hot water that may have something on it that will stain if not pre-treated. It's also important as a guest for you to know that you should always let a host know if something has been damaged, so they have an opportunity to deal with before it's too late. For instance, it's not uncommon for women to get some blood on the sheets when they have their periods. While it may be embarrassing to the guest to mention it, guests should overcome that embarrassment and let the host know ASAP so they can deal with it in whatever way they choose, rather than just letting the blood dry on it so it never comes out, meaning you'll be asked to pay for new sheets, or trying to deal with it yourself in an inappropriate way, like pouring bleach on it, thereby maybe ruining it and getting bleach stains on other stuff in the process. Guests have been charged for damages that simply resulted from them trying to remedy something themselves and making it worse, rather than respectfully notifying the host. Even if you accidentally wreck a towel or something, a host is far more likely to just chalk it up to normal wear and tear if you're forthcoming about it. What makes hosts mad is when guests try to hide the damage, or don't bother to mention it.
I will say, as a new, first time Airbnber with no reviews, as well as being young, you may have a difficult time getting a host to agree to having visitors or extra guests, but you can certainly give it a try. Message back and forth with the host before committing to book a place to make sure it will work for both you and them.
But do be honest with the host about everything- you seem like a nice, responsible person and I can certainly sympathize with wanting to live like a local and have a few people over at some point.
