What term describes the combining of items into real property that are not fixed or fastened?

The term that describes the combining of items into real property that are not fixed or fastened is constructive annexation. This concept refers to the legal principle where items, although not physically attached to the real property, are treated as part of it due to their intended use or purpose. For instance, items like tools or furniture that are placed in a property can fall under this category if they are deemed essential to the property's use or function.

Constructive annexation essentially considers the intent behind including these items within the property context, with the understanding that they contribute to the property's overall utility or functionality, even if they are not permanently affixed. This term is particularly important in real estate transactions and law, as it can affect ownership rights, value assessments, and property definitions in various situations.

The other options, such as constructive eviction, refer to a legal principle regarding tenant rights and landlord obligations, which does not pertain to property item combinations. Real property incorporation, while it sounds relevant, is not a recognized legal term within this context. Accessory structure describes buildings or constructions that are supplementary to a primary building but does not focus on the idea of combining loose items into real property. Therefore, constructive annexation is the appropriate term for this concept.