What do you do with long distance family?

I love my family, including my in laws! They are all wonderful people who I appreciate immensely. I am trying to sort out my emotions regarding the time they visit when the baby comes. My husband and I just celebrated our 1 year anniversary and my brother in law (from overseas) has "popped in" for a visit twice in the last 3 months for a month at a time. So far, he has lived with us 2 months since we have been expecting and plans on returning in 3 months when the baby arrives. All of our family will be coming from overseas, so it's expected that they stay  for a bit but after having my bil come unannounced for so long already, I feel desperate for my space and my alone time with my husband. To be honest, I'm dreading having the family come in Dec because I'm afraid that I will feel the pressure to cook, clean and host and that my husband and I won't get to enjoy the time with our new little one before we have to go back to work. I want to include our family and I don't want to be crazy controlling, I want them to feel free to enjoy the celebration but I don't know how to communicate that any visit more than 2 weeks becomes wearisome for me, especially during a time that is naturally taxing. Does anyone have experience with communicating boundaries without squashing the family's joy or making them feel unwelcome? I want them to feel welcome, but I guess I "expect" them to be sensitive in not overstaying.