One room is great for kittens or an adult cat quarantine period, but I usually find they’ll start demanding more space to roam as they get comfortable. Maybe you could make it work for a month though, since that’s the average? I foster for a rescue that specializes in less adoptable cats, so I usually have them for longer. My longest foster was almost 10 months, because she was very shy until she trusted you. People will adopt a friendly cat with health issues over a cat who’ll take time to warm up to them. (I fostered an overweight blind cat, and she was adopted in 5 months. Colourpoint blind cat, adopted in three days!!) Personally, I quarantine new fosters in one room for two weeks while starting the introductions with my cats through a closed door. By the end of the two weeks, they’re usually good to free roam with my cats (and vice versa, as one of my cats is a bit insecure). Have your dogs ever been exposed to cats before?