You only accept a guest if the timing and circumstances work for you and you are comfortable with the inquirer after reading their profile and/or communicating further with them.

You simply tell them you are unavailable. You are not obligated to host a constant stream of people or to accept a guest at a time that is not acceptable to you. The idea is that the network will grow to offer many options in each locale, and that most of us will find something available where we are needing it. AND, we can all help to build the network by spreading the word to friends and acquaintances, and through whatever means we have, so that the network grows to benefit us all.

No, many of us are perfectly happy with a breakfast of fruit, coffee or tea and cereal or toast---or with a nice selection of options available to serve ourselves in our own time frame. Simply make it clear in your profile and in your discussions with the visitor who is coming, what you will be providing.

The arrangements you make for giving your guests access to your home depend entirely on your particular set-up. Obviously, if they are using the entire property in an exchange, they will need access, though you can certainly make certain areas off limits. Many exchangers even arrange to exchange cars and care for one another's animals. Those are details for you to work out with your guests.

If you are hosting 1-3 nights, you may give access only to their guest room within the hours you are available, use the help of a maid or manager, or whatever works for you and your guests.