In general, you want less than a 60-day average collection period. Learn how to record retention receivable and payable, and why it can be essential for your construction business.5. 6. Enter receivables from third-party payers for contract settlement (Accounts 1050 through 1059). 6. 7. Enter pledges and other receivables net of estimated. Enter invoice number up to 12 digits long. Date: Enter date the invoice is prepared. We get an answer of 1.6. Use this form if you are administrative or fiscal staff needing to manage accounts receiveable contracts (revenue). Dunning is based on dunning levels, which can be determined for each receivables item. A taxpayer is not required to include in income the amount of a retainage until final acceptance of the project under the contract occurs.