1. A hand-propelled printer, comprising: a scanner configured to scan a first copy of a project document including updates and configured to generate update data from the project document, wherein the update data is used to update a stored version of the project document in a database; a position module to determine position data of the hand-propelled printer in response to movement of the hand-propelled printer on a second copy of the project document, wherein the position data includes a location and an orientation of the hand-propelled printer relative to an origin and an initial orientation; and a processor configured to receive the update data corresponding to the updates made to the first copy of the project document and accessed from the database and configured to communicate print data to a print mechanism to selectively print the updates at correct locations on the second copy of the project document according to the position data.
6. The hand-propelled printer of claim 1 wherein the processor determines a reference point of the project document based on scan data received from a scan head.