Whatever property you plan to purchase, surveying allows you to see exactly what the land underlying the property is. You should know whether any nearby entity has an easement - a right pass through to any part of the land you plan to purchase, or whether there is an encroachment - a portion of someone else's property intruding on what you plan to buy. There may also be other covenants - conditions and/or restrictions tied to the land, all of which are essential to know before making a purchase.
Commercial real estate surveying
Easements and restrictions can cause more headaches for a buyer than zoning regulations, particularly if you plan to renovate or expand the property. Look for a survey from ALTA - the American Land Title Association, which is prepared by a licensed surveyor in accordance with the Association's standards. Typically, title insurers want to see the results of an ALTA survey before issuing a commitment. The survey will include information on encroachments on to the property you intend to purchase; encroachments the property you intend to purchase has on neighboring properties; and easements that affect the intended property.
Residential real estate surveying
Surveys should be current; many lenders will not honor one more than six months old. Most residential real estate purchasers obtain house location surveys, which are cheaper. However, the title insurance firms will not consider these surveys in coverage of encroachments and boundary line disputes. To get title insurance that covers these issues, you should also get an ALTA survey when purchasing residential real estate as an investment.