The bathroom is often the only sensible tray site in a small flat: it is quiet, its floor wipes clean, and it already belongs to the household's washing routines. It can serve her well for years, but only if two problems are solved honestly. She must always be able to reach it, and the room's moisture, steam and cleaning smells must be managed, because the corner that is convenient for you is the airspace she has to toilet in.
Guaranteed Access Comes Before Everything Else
A tray she cannot reach is worse than no tray at all, because she will choose a reachable corner instead and a habit you do not want will have begun. Fix the bathroom door so it can never swing fully shut: a doorstop, a wedge, or a latch that holds it ajar wide enough for her at all hours, including overnight, when guests stay, and when anyone cleans the flat. Check the arrangement from her side, not yours; a door that drifts closed on a slope or gets pushed to by a visitor defeats the whole setup. Keep her route to the door unobstructed as well, with no laundry baskets, mops or drying racks narrowing the hallway she crosses to reach it. If the door must close for a shower while guests are in the flat, keep that closure brief and predictable rather than leaving her locked out for a morning.
Daily Scooping, a Litter Mat and the Right Tray
In a small flat, odour has no distance to travel, so scoop the tray daily as a fixed habit tied to something you already do, such as the morning bathroom routine, and wash the tray out regularly with mild, unscented cleaning rather than perfumed products whose smell clings to the plastic. Choose a tray large enough for her to enter, turn and dig comfortably, with sides suited to how she uses it, and keep the litter itself unscented, because a scent chosen for human noses can be a reason a cat avoids the tray. Set a wide mat where she steps out and shake it into the tray or the bin every few days; granules caught there are granules that do not reach the bedroom carpet. Top up litter little and often to a steady depth rather than letting it run low and then replacing everything at once, which changes the feel of the tray under her paws.
Moisture, Steam and the Case for a Second Tray
A few physical details make the corner pleasanter for her and for you. Stand the tray on a washable mat that extends beyond its edges, so litter dust and the occasional overshoot land on a surface you can lift and rinse rather than on grout lines that hold odour. Keep a small covered bin within reach for scooped waste so the daily habit takes seconds, and store the litter bag sealed against bathroom damp.
A bathroom's weaknesses are damp air and strong smells of the human kind. Run the fan or open the window after showers so steam clears rather than settling into the litter, keep cleaning sprays and scented products stored in a closed cupboard away from the tray corner, and never place air fresheners near where she toilets. If the flat holds more than one cat, or if she dislikes sharing her toileting spot with household traffic at busy times, a second tray in a screened hallway corner, behind a room divider or a curtain, is worth the small space it costs, and it also covers the moments when the bathroom is occupied. Those tray chores can be divided between the household in KinsLe, where Care Teams assigns each one to a named person and marks it done, so her corner never depends on one memory.