revenue of transaction price

T company regularly sells custom boats at a quoted price of 19,800 each (standalone price). They offer the buyer a top quality bike to take along with the boat. They also offer to recalibrate the boat's engine only once after 6 months of purchase. The sailor purchases a sail boat for a price of 18,000 accepts the bike offer, and chooses company T to do the calibration. Company T charges the same the sailboat irrespective of whether or not the customer accepts the bike and the calibration service. The Calibration service and the bike EACH is estimated to have a standalone selling price of 1,100. The customer paid $18000 cash upon delivery of the sail boat and the bike on September 1, 2018. Company T preforms the calibration service on Feb 4, 2019. prepare the journal entries for 2018 and 2019