Colson Corp. manufactures and sells custom storm windows for enclosed porches. Colson also provides installation service for the windows. The installation process does not involve changes in the windows, so this service can be provided by other vendors. Colson enters into the following contract on June 1, 2018, with a local homeowner. The customer purchases windows for a price of $4,700 and chooses Colson to do the installation. The price of the installation service is estimated to have a fair value of $1,200, though Colson provides a 30% discount. The customer pays Colson $4,000 (which equals the fair value of the windows, which have a cost of $2,300) upon delivery and the remaining balance upon installation of the windows. The windows are delivered on August 1, 2018, Colson completes installation on September 15, 2018, and the customer pays the balance due. Prepare the journal entries (noting the date for each entry) for Colson in 2018.