Setting your sights on the right site
S.A. "Sam" Jernigan doesn't regret buying a 20-acre lot in Grass Valley, Calif., for her dream house. But the process, she admits, is "not for the faint of heart."

"I'm an interior designer, and my husband was a Realtor, so we knew something about buying land," said Jernigan, whose husband recently succumbed to cancer. "Even so, we had delays, which cost money. You know that rule about adding 10 percent to your budget to cover potential problems? It's a good rule."

If you intend to buy a lot for your new house, finding it is your first hurdle. Jernigan shopped the Multiple Listing Service, but that followed many Sunday drives to pinpoint the area.

"Often, a lot isn't listed, but the owners or their heirs plan to sell," said Lake Bluff, Ill., homebuilder Orren Pickell. "We've put business cards in mailboxes and knocked on doors. Often, the best lots are the ones that are hardest to buy."

Carol and Michael Bilder found their New Buffalo, Mich., lot through a Realtor who knew its owner had died. They waited two years for the estate to settle before they could buy the lot, demolish the old house on it and hire Pickell to build a new one. Their house is slated for completion in December.

"It's glorious, on 200 feet of Lake Michigan beach," Carol Bilder said. "It took a while for the estate to settle, but we're glad we waited. They're not making lakefront land anymore."

Sometimes, a lot remains a diamond in the rough because builders passed it by.

"We got a great deal on ours because it had a low front section," said William J. Hirsch Jr., North Carolina architect and author of "Designing Your Perfect House: Lessons from an Architect." "So we built the house at the back of the lot."

Not every lot is buildable, though. Before you buy, consider these potential pitfalls:

Can you get there from here? Unless you are the rare homeowner who commutes by helicopter, your lot needs automobile access.

Jernigan found an old aerial map of her lot that showed a rough-cut road. County officials told her the switchback-style road could become an entrance to her house, but could not serve emergency vehicles. She had to secure an easement for them.

Then determine how the future driveway will affect your floor plan.

"The house design starts with the garage, which is often the biggest 'room' in the house," said Hirsch. If the driveway/garage location denies you the floor plan you want, go back to square one.

Liquid assets. Equally important is access to community water and sewer lines. Lacking those, determine if your lot can have a well and septic field.

"Ask local well drillers how far they've drilled to reach water in your area," said Hirsch. "Consider making water access a contingency of the sale or requiring the seller to drill the well first. Otherwise, you may buy a lot without enough water."

To determine septic field feasibility, you need a percolation test. A contractor measures the absorption rate of the soil on the site of your proposed septic field.

In areas where hard soil prohibits septic fields, homeowners install septic holding tanks. This is the norm in Lake Geneva, Wis., for example.

In addition to water and soil conditions, tests can reveal all sorts of underground surprises. But, as Hirsch illustrates in his book, a test-hole dig may be fruitless. It only reveals what is below the dig, while a boulder or old washing machine lurks a foot away.

Don't take electricity and natural gas access for granted, either. Reaching these sources may be difficult and costly.