When I started out, my kids were still living at home, and the way my house is laid out, you had to walk through the living room and the dining room to get to the bathroom or kitchen. Between my kids and the friends they invited over, there was frequent foot traffic right through the middle of my "office."
I found the setup extremely stressful, but I knew that making my bedroom my office wasn't the answer. With my desk and computer in my room, I never really felt like I left work, even when I pulled the blankets up over my head at night. But in the living room or dining room, my lack of privacy got to me so much that I would occasionally "borrow" a family member's pied-a-terre in a nearby city for a few days just to be away from everyone. And that was a drastic step, because that apartment didn't (and still doesn't) have Wi-Fi.
Eventually, my daughter grew up and moved out, and I turned her old room into my office. The change was dramatic and immediate. I leave my door open all the time, but simply knowing that I can shut it and block the world out a little better makes the workday far less stressful. And there's no foot traffic, because it's not on the way to any other room in the house.
I think having an actual office was a psychological cue for others in my life, like it made my career more official (even though I had been doing it full time for a couple of years by the time I had my office).
Whatever your working setup, it's important to establish boundaries, like office hours and a space that's solely for work, even if it means putting up a room divider to give you private space in a common room. Self-employment is hard work, and it's important that you ensure that the people in your life take your time and your space seriously.
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