do i have room for a chow?

hello everyone i am new to this forum. I currently have a 7-8 year old saint bernard male. hes the most lovable drooly boy ever. He is fairly small for his breed (only 104lbs) the spca we got him from said that he is a mix which explains his size. Anyway, we have recently been thinking about getting him a little brother, a chow chow puppy to be specific. the only thing im womdering is would it be okay to have both these dogs in the same apartment? we live on a first floor apartment fairly sized, two bedrooms a decent sized living room and kitchen and a nice size fenced in yard. our saint bernard loves it he goes inside and out as he pleases and has the neighbors dogs to play with. we made the second bedroom an office/his room. i know our saint lives very comfortable here but i dont know if a chow would as well, especially at the same time. this would be our first time having a chow. and i just want to make sure i evaluate all the situations before making my decision.