While most surveys begin with a boundary survey, there are any number of options and tasks that the surveyor can perform. Intermediate points can be set along the property lines when an intervisable line of sight is needed for fence or wall construction. Topographic mapping for engineering or architectural development can be requested as well as elevation certification that complies with FEMA or County requirements. Construction surveying is needed to place homes, buildings, walls, utilities,and other improvements in their exact locations. Some sales contracts require an ALTA/ACSM survey that shows the boundary as well as all improvements, easements of record and any of the listed schedule B exceptions that are requested.