4.2.2.2.1. Existing Government Improvements.The presence of government-constructed buildings and improvements on the property on the date of value may significantly affect the analysis of market value. Proper treatment of improvements often turns on the legal effects of a lease, if one exists, as “any valuation should take into account the lease terms covering improvements” of significance to a reasonable buyer.247 But regardless of a contractual agreement, “the equitable principle which condemns unjust enrichment [may] prevent[ ] the value of [government-built] premises becoming a windfall to the owner of the land in the guise of fair compensation.”248 Depending on the facts of the acquisition, the appraiser may need to determine a buyer’s cost to remove such improvements, estimate any contributory value, or exclude them from consideration entirely, among other courses.249 Therefore, appraisers should request legal instructions on how to treat government-constructed improvements that predate the date of value.250