There are times when you should request copies of your records: 1  Permanent Change of Station. 2  Deploying. 3  Retiring.
0. EXPERT ANSWER. Double coincidence of wants refers to a situation in a barter system where the goods or services offered by a seller are exactly the same as that required by a buyer and vice versa.
The major limitations of Barter Exchange are: 1. Lack of Double Coincidence of Wants: Barter system can work only when both buyer and seller are ready to exchange each otherâs goods. For example, A can exchange goods with B only when A has what B wants and B has what A wants. However, such double coincidence is very rare. 2.