(a) Subject to the additional criteria of Subsections (a-1), (b), and (c), value under this chapter is:
(1) the fair market value of the property or service at the time and place of the offense; or
(2) if the fair market value of the property cannot be ascertained, the cost of replacing the property within a reasonable time after the theft.
(a-1) In the prosecution of an offense under Section 31.16 involving retail merchandise stolen from a merchant, the value of the stolen retail merchandise is:
(1) the sales price of the retail merchandise as stated, posted, or advertised by the merchant, including applicable sales tax, at the time of the offense; or
(2) the rental price of the retail merchandise as stated, posted, or advertised by the merchant, including applicable sales tax, at the time of the offense plus the cost of replacing the retail merchandise within a reasonable time after the offense.
(b) The value of documents, other than those having a readily ascertainable market value, is:
(1) the amount due and collectible at maturity less that part which has been satisfied, if the document constitutes evidence of a debt; or
(2) the greatest amount of economic loss that the owner might reasonably suffer by virtue of loss of the document, if the document is other than evidence of a debt.
(c) If property or service has value that cannot be reasonably ascertained by the criteria set forth in Subsections (a), (a-1), and (b), the property or service is deemed to have a value of $750 or more but less than $2,500.
(d) If the actor proves by a preponderance of the evidence that the actor gave consideration for or had a legal interest in the property or service stolen, the amount of the consideration or the value of the interest so proven shall be deducted from the value of the property or service ascertained under Subsection (a), (a-1), (b), or (c) to determine value for purposes of this chapter.