I think the city uses a software program to do it's real property assessments. I believe it's a canned program used by other municipalities. The assessor still go out because they have to Value things such as improvements as well as validate new construction. during acquisitions fair market value is used.  Fair market value is defined by the uniform appraisal standards. Appraisals are really best estimates of market value. The appraiser has a lot of leeway in terms of valuations adjustments to valuations and capitalization rates. In the eminent domain cases I've been involved with I have never seen a landowner recoup enough in terms of market value to cover his legal expenses. Most people Take the Money and Run because they can reinvest the money in a similar asset without paying capital gains taxes.  So if a landowner's asset has appreciated 200% over 20 years he can capture that increase without cap gain taxes