"In all instances the appraiser must investigate...private restrictions, zoning...and environmental regulations...because they may preclude many potential uses." the Appraisal of Real Estate, 311 (12th ed. 2001). When analyzing the highest and best use of the Subject Property, we consider the following: Whether the land should be developed; if the land should be developed, what kind of improvements should be built; and should the existing improvements be maintained in their current state or altered to make them more valuable. the Appraisal of Real Estate, 306 (12th ed. 2001). Minnesota Court considers the three traditional approaches (cost, income, and sales) to determine market value as outlined in Equitable Life Assurance Soc'y v. Ramsey County, 530 N.W. 2d 544, 552 (Minn. 1995). Whenever possible, two approaches to market value should be considered because they can serve as useful checks on each other. Id., 530 N.W.2d at 553. As the Court stated in Hedberg v. County of Hennepin, 305 Minn. 80, 232 N.W.2d 743 (1975), "evidence showing a reasonable probability" of permissible use under applicable zoning laws is required to rely upon future changes of zoning in valuing a property.