@jalice4ever - put only the essentials in. I had bed, shower, toilet, stove, fridge, 3 counters, desk, computer, dining table, penguin TV, 2 cheap chairs, an easel and a mirror. And a Nano trash can. No sink. I divided off one side of the room to make a 3x8 garden since my sim loved the outdoors. She spent a lot of time out there and it kept her happy. Oh, yes, I also gave her a giant bear to talk to. Childish trait. Later, if you want more stuff like the microscope or fitness equipment she have to move some of your stuff out to make room. Your sim can't go outside the space but you can swap objects into and out of your inventory or just set them outside the house. It doesn't really take many objects to care for their needs. I have finished the challenge and my sim is living in her mansion. She takes a LOT more time going from one place to another to tend her needs then she did when living in that little room.