Tycoon Remove button not working ?

So this is a bit free modelish button but i reedited it and what i want it to do is ontouched it removes the object BUT doesn't buy it. When players enter the game they see the part and they need to remove it with the button, but not buy it.

model = script.Parent.Parent.Parent.Door
Upgradecost = 5

upgradeStuff = model:clone()

wait(1)

model:remove()
owner = script.Parent.Parent.Parent.Parent.Owner
local ting = 0

function onTouched(hit)
	if ting == 0 then
	ting = 1
	check = hit.Parent:FindFirstChild("Humanoid")

	if check ~= nil then
	if hit.Parent.Name == owner.Value then
		local user = game.Players:GetPlayerFromCharacter(hit.Parent)
		local stats = user:findFirstChild("leaderstats")

		if stats ~= nil then
			local cash = stats:findFirstChild("Cash")
			if cash.Value > (Upgradecost-1) then

				cash.Value = cash.Value - Upgradecost
				upgradeStuff.Parent = script.Parent.Parent.Parent.Parent.PurchasedObjects
				script.Parent.Parent:remove()

			end
		end
	end
	end

	ting = 0
	end
end

script.Parent.Touched:connect(onTouched)

i get error: Workspace.Script:2: attempt to index field 'Parent' (a nil value)