use metrash app or go to traffic department get the token and wait for your turn and when the number appear on the display go to the respective counter. give the ID's of the both buyer and the seller and the old istimara/ registration card to the officer and they will do rest of things and sign on the paper they give you and pay 200 QAR. that's it!! and you will receive text message on the registered mobile. they will issue the new istimara on the spot