What is the test for meeting the burden of showing that there is a reasonable probability of a zoning change and that it was reasonable and proper for an appraiser to consider this factor in determining the value of the subject property?

We hold that respondents met the burden of showing that there was a reasonable probability of such a zoning change and that it was reasonable and proper for their appraiser, Henderson, to consider this as a factor in determining the market value of the subject property. (Cf. People ex rel. Dept. of Public Works v. Donovan, 57 Cal.2d 346, 352, 19 Cal.Rptr. 473, 369 P.2d 1; Los Angeles Etc. School Dist. v. Swensen, 226 Cal.App.2d 574, 581, 38 Cal.Rptr. 214.)