Just wanting to know if it takes like, hours, a day, days, or weeks? Not expecting it to sell immediately.
As Grandmaster said, codestones sell fast. Faerie quest items sell usually within one week to one month. Food sell fast, usually within one to five days. Gourmet food...takes longer, maybe one to two weeks.
Igloo items range really from stamps, to wearables, to gardening, so there's no real estimate you can make. Stamps sell decently quick, usually within the week. I can go on.
The thing to keep in mind is that cheap stuff that are used for quests will sell quickly, whereas expensive stuff generally take longer. You should sell most of your stock from the Igloo within a week.