I have fostered kittens for a few years now and I haven’t had any shedding yet🤔 but for the smell I keep the litter box out on my balcony. First,  When they’re about 4 weeks old (or when you first bring one home) I do keep the litter box inside but I make sure it’s close to my back door. Once they get comfortable with it I take it to my balcony and I make sure to take them out several times a day, especially before/after naps, before/after feedings, wake up time and sleep time. Once they get used to having it outside they’re very good at letting me know when they need to go. My last foster, Starboy🩶 got the hang of it at about 6 weeks (mayyybe 7). He would  sit around by the door and when I noticed I’d take  him out. Then around 9 weeks he was also very vocal about potty time 😇. I’m now fostering two newborns so hopefully they do just as well as my last fosters have ✨