Adopting a new or changing the existing local development plan is most often associated with an increase in the value of real estate. When selling the property, the owner of the property is obliged to pay a special fee (planning rent) in connection with the increase in the value of the property. This fee is collected by the commune head, mayor or president and cannot be higher than 30% of the increase in the value of the property. In practice, many misunderstandings and problems arise in the operation of this fee. The main cause is an incorrectly calculated and overestimated difference in the value of the property, which leads to undue claims by the commune against the property owner. Art. 36 and 37 of the Act of 27 March 2003 on Spatial Planning and Development states that the condition for collecting a one-off fee (planning rent) is the need to simultaneously meet the following conditions: increase in the value of real estate as a result of adopting a new or changing the existing local plan, specifying in the local plan the percentage increase in the value of the property, constituting the basis for calculating the amount of planning rent or sale of real estate by the current owner or perpetual usufructuary