[2021] Problems with lack of space

Welcome to the forum @Badger Guardian There is a spell dropping in the Spire of Eternity that allows you to send most buildings back to the inventory so you can make room for rearranging your city. It is one spell per building and some buildings cannot be teleported into your inventory: evolving buildings, Ancient Wonders and the main buildings e.g. Bararacks, Trader etc.