When is the supplication made in the Istikhara or Hajah prayer: after the Taslim from the prayer, or during prostration, or before the Taslim?

The supplication for Salatul-Istikhara (prayer for guidance) and Salatul-Hajah (prayer of need) should be recited after the Salaam (concluding salutation) of the prayer, according to the more accurate opinion among scholars. This is based on the Prophet's (peace be upon him) sayings in the narrations concerning Istikhara and Hajah prayers: "Then let him say" and "Then let him praise Allah," both of which come after his command to perform the prayer. The particle "thumma" (then) implies a sequential order with a slight delay, indicating that the supplication comes after the Salaam. Some scholars, such as Ibn Hajar and Ibn Taymiyyah, held the view that it is permissible to make the supplication both before and after the Salaam, with Ibn Taymiyyah preferring it before the Salaam.