My room is 12 x 10, I think, and I've got a bed, 3 bookcases, a dresser, a heater (looks like a Franklin stove and I love it, so it stays), a 5 ft dollhouse on a 4 ft cabinet, and a 7 ft sofa, along with an end table for my computer and a plastic tree or two. I'm actually layering the furniture at this point. I have the bed behind the fridge, separated from that with the computer table and a folding screen, and between the bed and the wall I put two of the bookcases with the third one back against the bed on the other side of it.
I guess you could say in this tiny room, I've made a kitchen, a bedroom, a living room, and a dressing area. I will say one thing about small spaces - when you don't have storage in the kitchen, hanging as much as possible on the walls is incredibly helpful and going against common practice, putting "walls" up in a small room actually gives me more space to put things, as I have have made some artificial walls to push furniture against. Of course, my bedroom is only as wide as the bed and the "living room" space is only 9 x 7 and my dressing area is behind the bathroom door right in front of the dresser.
I like tiny houses and from looking at those and some trailers, I think the best place for a kitchen is at the end, where you can make it an L- or U-shape. I've seen some tiny house kitchens that have more space than my kitchen.
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On this trailer, I'd have put the stove over on the other side of the sink at the end of the counter there, but that's just me.