Word of advice:
"When homeowners or other non professionals try to locate property lines themselves, they usually have problems as there is no way they can be sure that property stakes (irons) haven't been moved, if they are they are still there. Often they are gone (due to various reasons)."
They are structures that separate your property from neighboring properties like fences or walls. To specify a property boundary, you can strike a agreement with your neighbor on the specifications.
Replicate the method for the other three corners, even where no right angle exists. This way the boundaries of your house can be measured. Keeping a straight line as a point of reference, you can measure curved corners.