If a recipient purchases with cash an essential item, and such purchase under the rules and regulations of the department would have entitled him to a special need allowance each month to meet monthly installments on such purchase had he paid for the item in monthly installments, the recipient shall be considered to have purchased the item from his personal property holdings, and shall be allowed to place in his savings, each month, without deduction from his grant, an amount of income equivalent to the special need allowance he would have been granted had he paid for the item on a monthly installment basis, if he reports the purchase to the county department within 90 days

after the date on which it was made. The income placed in his savings shall be considered personal property.

The county department, for good and sufficient reason, may extend the period during which a recipient may report a purchase under this section. The department, in its rules and regulations, shall indicate what constitutes good and sufficient reason for extending that period.