In spite of the best efforts of everyone involved in a real estate transaction, sometimes the time periods set out in the contract for the fulfillment of certain terms cannot be met. The CAR contracts explicitly state however that, for example, contingency time periods may only be extended, modified, altered or changed by mutual written agreement. Further, neither the agreement nor any provision in it may be extended, amended, modified, altered or changed except in writing signed by buyer and seller. Not only does the contract require a writing but good business practice dictates that an extension be put in writing to avoid confusion and disagreement over the terms of the extension. This form allows the parties to appropriately document in writing an extension.