Is a customer entitled to refuse to take delivery of doctors' garments after they have been tailored and manufactured, or to alter their pre-agreed specifications, such as by adding requests that were not previously present, or changing the color, or the type of fabric, or the style and measurements of the garment?

The transaction mentioned in the question falls under the contract of Istisna' (manufacturing order), which is a binding and obligatory contract for both parties if its conditions and pillars are met. This was stipulated by the Islamic Fiqh Academy in its resolution no. (65). It was preceded in this regard by "Al-Majallah Al-Ahkam Al-Adliyyah" (The Ottoman Civil Code), where Article (392) states: "Once the Istisna' contract is concluded, neither contracting party has the right to revoke it." The origin of this binding nature is based on what Abu Yusuf held regarding obliging the manufacturer to perform the work and the buyer to accept, in order to prevent harm to either party. Based on this, the client does not have the right to withdraw their order or amend its terms after the manufacturer has begun or completed the work, and the manufacturer has the right to compel them to receive their order and refuse its return.