One of the requirements to obtain a building permit in the City of Cincinnati and many other jurisdictions for new home construction is a survey of the property stamped by a registered surveyor. The document the surveyor provides is called a plot plan and it indicates the extents of the property lines, existing and proposed elevations for the structures on site, the locations of new walks and driveways, sewer line inverts, and and setback requirements. Below is a screenshot of the plot plan for the Starter Home 2.0 project and a photo showing an 'x' spray painted over a piece of rebar marking where the existing corner of the property is located.
(above) plot plan for property
(above) x marking a corner of the property