What principle indicates the increase in property value due to economic assemblage?

The concept that indicates the increase in property value due to economic assemblage is known as plottage. This principle refers to the increase in value that is realized when two or more adjacent properties are combined into a single larger parcel. The combined property can often be worth more than the individual properties separately due to several reasons, such as improved usability, better overall functionality, and more efficient use of land.

In an economic context, when properties are assembled, they can benefit from economies of scale, increased visibility, or enhanced development potential, thus leading to a noticeable increase in overall market value. This is particularly relevant in real estate development and investment, where combining properties can facilitate larger-scale projects that would not be feasible with smaller, separate parcels.

The other principles mentioned relate to different concepts in real estate, such as the contribution of specific features to overall property value (contribution), the impact of a lower-priced property on the value of a higher-priced property (progression), or vice versa (regression). However, none of these directly pertain to the value increase associated with the combination of properties, making plottage the correct choice in this scenario.