The aim of the research is to reveal the effects of irregular urbanization and environmental effects and the extent of their impact on the market values of real estate unit prices. The research relied on the descriptive analytical approach to determine the environmental effects that affect the prices of real estate units. As well as descriptive and quantitative to determine a model that reflects the market prices of the mixed real estate units in terms of the current activity of these units, through what the objectives of the study sought to identify the informal economy through irregular urbanization and its effects on the environment. As well as identifying irregular urban development and its impact on real estate market values. In addition to a presentation of the elements of the proposed real estate evaluation, the study relied on the analytical descriptive approach, and the study population is represented in the Sharabia area as one of the regions of Greater Cairo, and the focus of the study is on real estate units within the mission (Al Sharabia 1) only, which consists of five sheikhs, and the sample was selected and approved. The stratified random sampling method, which is considered one of the best and most accurate types of samples in representing the heterogeneous statistical population with the total sample size drawn. The study reached a conclusion for some indicators and the extent of their impact on the economy and the environment by examining how to link the relationship between the irregular urban development and the economic and environmental effects, which highlight the extent of the economic and environmental return on the state to explain the changes that will help the state in controlling the prices of the Egyptian real estate market, as well as This model will serve multiple entities at the state level.