NOt sure, but IIRC, we often see him entering stage right on the street scenes, while Rosita enters stage left (and maybe Zoe, too). My hunch is that Rosita and Zoe live in another building downt he street, while CM lives the other direction. Do we have address for Hooper's Store? Because that would help us narrow down numbers, whether they go up or down.
If Zoe, Rosita, and Telly's place also has 3 floors, then it would make sense that they all live int he same apartment to the left (from the viewers' perspective) of 123 Sesame, while Cookie Monster may live to the right, possibly int he same building as Elmo. Assuming it's a three-story, with ana partment on each floor, who else might occupy that building w/Cookie Monster and Elmo? Or do we joke that Elmo's made enough money his faily owns two floors or a whole building
We've seen Cookie Monster's mom & at leaast a drawing of Elmo's parents, BTW;has Cookie Monster's dad ever been mentioned?
Baby Bear's is confusing b/c beng from the story, there should be woods near his home. But, maybe his dad and mom commute in tow ork each day and he's in the daycare/preschool near SS. That would make a lot of sense, actually, now that I think about it. And you can probably take a subway from wherever in NYC Sesame Street is and get to the country prettye asily.
OTOH, maybe SS is just on the outskirts of town and you can get to the woods easily, as whent hey were gong for a hike.