Dr. Monzer Kahf, a prominent economist and counsellor states: “If the plans of construction are approved and the land is owned by the developer, it can sell on plans. However next sale must be after construction begins so that there is materiality of at least beginning of building whose part is been sold by the first buyer. This is in my opinion permissible as mentioned above. What is not permissible is sale before plans are final and the land is owned actually as this may lead to disputes over changes or inability of obtaining the land. We have legitimate reason to apply the rule of “do not sell what you do not own” in this case. Once the plans are there and the land is owned the sale is then a sale on Istisna’, it is permissible. Second sale by first buyer and subsequent sale require an added substance that is the beginning of construction because without it you are again selling a thing specific now (not simply on description as in Istisna’) that has no substance that started to exist. In other goods, because we are dealing with real estates the first sale is permissible and the second and subsequent sales are also permissible but with this added condition. This rule does not apply to mobile goods as we need actual possession for them before any second sale.”