The aim of this paper is to analyse the completeness of data contained in the register of real estate prices and values. Transactions concerning parcels with residential buildings located on them were studied. On the basis of, among others, data obtained from this register, real estate valuers evaluate real estate. The following market characteristics were selected for the analysis: transaction price, usable area, year of building construction, construction material of building walls, number of storeys, plot size, and others. The data were obtained from the District Office in Koszalin. The study was conducted on the example of Koszalin district in the years 2010‒2016. The technique of quantitative and qualitative analysis of documents was used in the study.