I used to store mine under a roof, open sides, although the loader hung out in the weather. Now at the new house, I dont have a covered area yet, so it's in the weather.
Does it matter? I know my old Kubuta would absolutely get water in transmission around the gear shifter boot. So, it does matter some.
I will note, Kiotis paint isn't very durable, so maybe cover is needed, and I plan to construct something soon-ish.