(a) Whenever feasible, and except as otherwise provided by law, debts owed to the United States, together with interest, penalties, and administrative costs as required by this regulation should be collected in full in one lump sum. This is true whether the debt is being collected by administrative offset or by another method, including voluntary payment. However, if the debtor is financially unable to pay the indebtedness in one lump sum, payment may be accepted in regular installments. FMCS will obtain financial statements from debtors who represent that they are unable to pay the debt in one lump sum. If FMCS agrees to accept payment in regular installments it will obtain a legally enforceable written agreement from the debtor which specifies all of the terms of the arrangement and which contains a provision accelerating the debt in the event the debtor defaults. The size and frequency of installment payments should bear a reasonable relation to the size of the debt and the debtor's ability to pay. If possible, the installment payments should be sufficient in size and frequency to liquidate the Government's claim in not more than 3 years. Installment payments of less than $50 per month will be accepted only if justifiable on the grounds of financial hardship or some other reasonable cause.

(b) If the debtor owes more than one debt and designates how a voluntary installment payment is to be applied as among those debts, that designation must be followed. If the debtor does not designate the application of the payment, FMCS will apply payments to various debts in accordance with the best interests of the United States, as determined by the facts and circumstances of the particular case, paying special attention to applicable statutes of limitations.