An RV that has last moved decades ago, doesn't have wheels anymore, has been built around (terrace etc) and is basically part of the land plot is still a vehicl

An RV that has last moved decades ago, doesn't have wheels anymore, has been built around (terrace etc) and is basically part of the land plot is still a vehicle? Laws of my country clearly say it's no longer a vehicle if it didn't move for a long time or can't move anymore, and thus has to be registered and permitted as a building. The laws also say it is a building and not a vehicle if it performs the function of one.