If you have two surveys performed on the same property, the two will nearly always have slight differences. Land surveying measurements are always subject to error which is influenced by everything from the weather at the time of survey to the equipment used for conducting the field measurements. In land surveying, measurements are taken on landmarks. In two separate surveys, the same landmarks may no longer be present, or may have shifted.

A land surveyor will research the documents available about your land, including titles and previous surveys. The next step is to physically measure the property and check the measurements against the previous records to determine if any discrepancies exist. A land surveyor is not a lawyer and is only bound to represent the facts based off of evidence measured and observed at the time of survey and compare the information to the documents of record. Any discrepancies may require lawyers and/or court activity.

One should always consider a new land survey when buying a piece of real estate. Even if the mortgage company or title insurance company do not require a new survey, an accurate current survey will provide valuable details specific to the property. One should be aware of any boundary discrepancies which may affect the value of your property before purchasing. Any disputes about the boundaries of the property should be settled before you agree to purchase, or face legal headaches later.

One may also want to consider having a land survey done if you are planning to sell property. It is especially important in areas where road access is questionable. Determining the status of roads onto your land can help your realtor determine the marketability of the property. Shoreline footage and acreage are two more selling points which are measured by a land survey. Some buyers might put in an offer contingent on a survey. If you have the survey done ahead of time, you can save time and increase the chances of selling your property quickly.

Before building a shed, fence, or other structure on the edges of your land, consider having a land surveyor mark the exact edges of your property. You can be assured not to build on your neighbor's land and not encroach into the neighbor's land. No legal protection is afforded for using a fencing contractor to determine your property lines. 

Subsequently, if your neighbor is building a structure and you believe it to be on your property, have a land survey completed. The survey is the first step toward resolving the problem and ensuring that your land remains without encumbrances or encroachments.

Using an outdated survey to determine any aspect of a property greatly increases liability. Newer measuring techniques, including GPS, yields surveys with a higher degree of accuracy. Structures are established or removed along with building improvements all of the time, one cannot be assured of any impact on a property without a current survey. Not all surveyors are the same, ask if the surveyor has current professional liability insurance and as to see the current insurance certificate