I'd like to request a sim who stays in a tiny sealed-off room with only the bare essentials and an easel constantly painting bizzarre and impossible scenes to scatter around the family's home. If I recall correctly you can stuff all of a sim's needs into a 4x3 room by using a high-end coffee machine as a substitue for sleep and keep it clean by using a dishwasher to dispose of plates and cups, since it never needs to be taken out.
So you'd need:
-a fridge (as I recall food is stored by the household, so restocking a more accessible fridge will keep the hermit from starving)
-a stove (just pray this guy doesn't start a fire)
-a counter for food preparation
-a coffee machine-laden countertop with a dishwasher underneath
-a chair and table for dining
-the easel for fun and profit
-shower for hygiene and bladder (a slovenly sim will be able to pee in the shower and save a tile that would go to a toilet)
-a wall-mounted telephone to ward off the Bunny (will not block use of other items and can be placed easily)
-Maybe a window or something at the end of the walkway that isn't being used by the phone, just so there can be some shred of human decency left to our mad artist.
Finding a way to cram a bookshelf in there to teach mechanical and cooking may help to prevent the sim's untimely demise due to fire or electrocution (washing machines are tough to repair) I think the table may not be necessary for eating, so long as the chair is of the dining chair category.
Also, I vote for house 3.