My sewing "studio" is a table which measures 40 x 24 behind the sofa in the living room. The space is hidden by the back of the sofa, my DH can be watching TV or reading while I sew, and when quilting, the back of the sofa supports the quilt weight. I can see the tv over the top of the sofa! Have a stack of plastic boxes under one side of the table to house tools and threads, and a 36" long bookcase with cubbies behind to house other supplies and books--corner windows provide wonderful light and air. My Viking Sapphire is on a placemat, which can be slide out of the way when using my serger, also on a placemat. When doing big projects, the not-in-use machine is removed to the floor at the end of the table. Cutting is done on a mat placed on the dining room table, mat is stored behind the corner cabinet. These areas are about 8' apart. I also use a rotating cutting mat which is 12" square next to my machine when it is more convenient.
We have a spare bedroom which could easily be used as a sewing room, and that is where the stash is stored! Would rather be downstairs with DH than upstairs by myself.
Putting away things is not a problem for us...think we tend to finish things up rather than leave them partially done when we need to put them away all the time.
Have fun quilting - find the best solution for you to living in a smaller space -- the cabinet link earlier in this thread is a wonderful idea. Sometimes we let space limit what we do -- I'll never be able to get a longarm in here! -- but still can enjoy sewing and quilting with plenty of room to do both.