If there is a written agreement to sell land without any specified time period to close the sale, then the time period is a reasonable one given the circumstances from which the agreement was entered into. The problem that I see from the question that you have written about is that the hand written contract may be deemed uneforceable because it is unduly vague with respect to the time of performance.I suggest that you have an addendum to this hand written agreement drawn up and signed by all parties to this land sale setting forth a specific time period for the sale of the real property to happen as well as the establishment of a formal escrow. The addendum should be dated.