(a) the award of more than one contract, or
(b) in contracts being awarded in separate parts,
the basis for valuation shall be either:
(c) the actual value of similar recurring contracts concluded over the previous fiscal year or 12 months adjusted, where possible, for anticipated changes in quantity and value over the subsequent twelve months; or
(d) the estimated value of recurring contracts in the fiscal year or 12 months subsequent to the initial contract.
5. In the case of a contract for lease or rental, with or without an option to buy, or in the case of a contract that does not specify a total price, the basis for valuation shall be:
(a) in the case of a fixed-term contract, where the term is 12 months or less, the total contract value for its duration or, where the term exceeds 12 months, the total contract value including the estimated residual value; or
(b) in the case of a contract for an indefinite period, the estimated monthly installment multiplied by 48.
If the entity is uncertain as to whether a contract is for a fixed or an indefinite term, the entity shall calculate the value of the contract using the method set forth in subparagraph (b).
6. In cases in which tender documentation specifies the need for optional purchases, the basis for valuation shall be the total value of the maximum permissible procurement, inclusive of all possible optional purchases.