Mason Artisan

Getting a stronghold built in the first place requires a mason, probably several. It’s perfectly natural for one to stay around after the thing is done and continue in the lord’s service, going from a hired hand to a permanent fixture. 
THE QUARRY: If you attract a mason, there must be a quarry somewhere nearby. This is the equivalent of the artisan’s shop. The quarry starts at 1st level, and the lord can improve it like any other shop. Having a mason on staff means you pay nothing to repair your stronghold after a siege. Your mason will make free repairs worth 250 gp per quarry level per week. A 3rd-level quarry therefore makes free repairs worth 750 gp per week (250 × 3 per week). Masons decrease the time required to improve your stronghold by 10% per quarry level. This time decrease can be combined with the carpenter’s benefit.