Getting the real shirt ID from Template ID

Help and Feedback Scripting Support
2

IIRC, aren’t able to get the shirt ID from the decal ID, however you can do the opposite, getting the decal ID from the shirt ID. What I would do instead, is create an IntValue inside of the mannequin and then iterate through all mannequins and give each mannequin the shirt ID to be applied.

For example:

for i,v in pairs(workspace:WaitForChild('Mannequins'):GetChildren()) do
    if v:FindFirstChild('ShirtID') then
        local shirt = v:FindFirstChild('Shirt')
        if not shirt then
            shirt = Instance.new('Shirt')
            shirt.Parent = v -- parent to the mannequin
        end
        shirt.TemplateId = 'rbxassetid://'..v.ShirtID.Value
    else
        warn('No ShirtID value was found inside of '..v.Name..'!')
    end
end

And then for your click detector,

clickDetector.MouseClick:Connect(function(plr)
    local value = clickDetector.Parent:FindFirstChild('ShirtID')
    if value then
        market:PromptPurchase(plr, id)
    end
end

A feature request for this has been created awhile ago but it wasn’t ever addressed.