How to get user's on-sale items?

I cant get exactly what you want but I did find something on how to get a users owned clothes. if this will assist you in anyway

local InventoryUrl = "https://robloxdevforumproxy.glitch.me/users/inventory/list-json?assetTypeId=11&cursor=&itemsPerPage=100&pageNumber=%x&sortOrder=Desc&userId=%i" -- used in a string.format thingy

-- In an event
local Inventory = HttpService:JSONDecode(HttpService:GetAsync(string.format(InventoryUrl, 1, Player.UserId))) -- function
for _, item in next, Inventory do
-- do stuff
end

Please take in mind that this was in a solution from 2019