The aim is to examine to what extent does the professional activity of the population and the economic activity of entrepreneurs affect the development of the apartments' market. The subject of the study are local real estate marketsthe sector of commercial investmentsresidential seaside apartments. Design/Methodology/Approach: We analysed data about real estate markets of Polish communes located in Central Pomerania. The values of the analysed indicators were calculated using Excel program and the results were presented in the form of Tables and Figures in Microsoft Excel and ArcMap. Findings: The results show that there is a relationship between the professional activity of the population and the economic activity of entrepreneurs in the tourist communes and the development of the primary and secondary real estate markets. The analysis shows that economic effects of tourism development can influence the income of the commune, an increase in local revenue achieved by entities that manage tourism, high professional activity of the population and economic activity of entrepreneurs as well as the diversification of the economy thus allowing to obtain independence from the economic instability. Practical Implications: The most important practical implication is the statements that there is a need to make new investments in seaside towns in which the tourist market is developing. Originality/Value: The analysis shows that economic effects of tourism development can influence the income of the commune with an increase in the local revenue achieved by entities that manage tourism.