Generally, a class A survey requires a 1:10,000 closure. So you you can have an error of closure of 1' for 10,000' traversed in a closed loop. When it comes to lost or obliterated corners, reestablishing the property line is somewhat methodical, but also includes some judgment by the surveyor. By survey law, the order of operations for reestablishing a property corner is 1. Monuments, they always control as long as they are within reasonable tolerances. 2. Distance. 3. Course (bearing). 4. Prima fascie evidence. That being said, property is subdivided in two ways in NC. By subdivision plat or deed with metes and bounds description. In platted subdivisions, we survey to the next property or two, then prorate distances. By deed, there are junior and senior rights. The out parcel always gets what the deed calls for, and the parent tract is left with what is left regardless. Two or ten good surveyors should come up with fairly the same reestablishment of a property corner. As a surveyor, our duty is to promote and protect the welfare of the public, so property lines should be reestablished the same, regardless of who hired you.