Does the option of the meeting place (Khiyar al-Majlis) apply when the buyer is also the seller (e.g., buying for one's child from the child's money or vice versa)?
Chapter on the Option of the Two Parties in Sale
Al-Mughni
Book of Sales
Primary text
If the buyer is the seller, meaning he contracts on both sides, the option of the meeting place is not established because he has assumed both ends of the contract, analogous to the pre-emption claimant (Shufi'iy). The contract becomes binding upon separation, whether intended or unintended, known or unknown, because the Prophet (PBUH) tied the option to separation, which has occurred.
Supporting text
There is a possibility that the option is established, and the contract is only binding upon separation, because separation is not feasible in this scenario since the seller is the buyer.