*Fath al-Qadir* explains Muhammad’s position through the loss of a desirable quality: in both murabahah and tawliyah the first price was represented falsely, so the buyer gains an option.
Example: the real first price was Rs 700, but goods were sold as tawliyah with Rs 900 claimed as the earlier cost. Muhammad does not automatically deduct Rs 200; the buyer may affirm or return the goods.
This differs from Abu Yusuf’s deduction in both types.