When determining the value of stolen property, what is fair market value?

Citing jury instruction CALJIC No. 14.26, the court in People v. Pena (1977) 68 Cal.App.3d 100, 102 defined the value of stolen property as fair market value of the stolen items: "'Fair market value is the highest price, estimated in terms of money, for which the property would have sold in the open market at that time and in that locality, if the owner was desirous of buying but under no urgent necessity of doing so, if the seller had a reasonable time within which to find a purchaser, and if the buyer had knowledge of the character of the property and of the uses to which it might be put.'" (Ibid., at fn. 1.)

The Pena court also cited CALJIC No. 14.27, which instructs in relevant part that "An expression of opinion on value by the owner may be considered by you in determining value together with any other evidence bearing on that issue. In determining what weight to give an owner's opinion, you should consider the believability of the owner, the facts or materials upon which the opinion is based and the reasons for the opinions. [] An opinion is only as good as the facts and reasons on which it is based. . . . [] You are not bound to accept an opinion as conclusive, but you should give to it the weight which you shall find it to be entitled. You may disregard any opinion if you find it to be unreasonable." (See People v. Pena, supra, 68 Cal.App.3d at p. 102, fn. 1; Miller v. People (1977) 193 Colo. 415, 417-418 [When determining the value of credit cards for purposes of a theft prosecution "[w]here there is no legal market, evidence of the illegal market price and other objective evidence may be considered"].)