Buying land can be very risky - far more so than purchasing a house. Land is subject to a variety of regulations and other problems that can affect your ability to build. Things that must be reviewed include:

• The lot must conform to zoning regulations to allow the construction of the desired home.
• If the property is not served by a municipal sewer system, you will need to install a septic system. Not all lots can support septics - and some that can will require very expensive systems - so it's crucial to have the required testing done before committing to close.
• The property must be served by all other utilities.
• The land should be dry and not subject to flooding.
• If the area is rocky or the topography is rugged, it is essential to have a thorough understanding of the costs of site work.
• Land financing is far more difficult to obtain than a regular home mortgage.
• There should be no moratoria or other restrictions against building - either in effect or pending.

Don't even consider buying a lot without the help of an experienced real estate attorney.