Solar orientation varies by climate, he added. "In a warm climate, you want your living area in the shade. In a cold climate, you welcome the sun," Hirsch said.
"Many of our clients want an English or walkout basement, so ideally the lot slopes from front to back," said Pickell.
The lot's slope dictates drainage of water.
"You can change the topography of your lot, but you can't change the neighborhood's drainage flow," Pickell said. "If an area is being rapidly developed and losing vegetation [which absorbs rainwater], you may have future water problems."
Drainage is one of the key factors gleaned from an architect's site analysis, Hirsch said.
"Many clients have told me they bought a flat lot," he said. "But the analysis showed it was not."
Wooded acreage. Wooded lots sell at a premium, but not every tree is a good one. And lot clearing is costly.
The Bilders called an arborist to identify the trees on their lot.
"It turned out most of them were scrub trees, so we removed them and plan to plant oaks and maples after the house is finished," Carol Bilder said.
An arborist can also alert you to local tree ordinances and tell you how to protect valuable trees' feeder roots from construction-vehicle damage.
Guidelines. A trip to your county or city offices yields a slew of rules that apply to your lot, from setback minimums to historic district guidelines. Scanning the Sanborn maps at your public library yields older data, like locations of burial grounds. A surveyor tells you the lot's dimensions and any easements or encroachments.
Subdivision covenants reveal neighborhood no-nos. If the seller doesn't have a copy, ask the homeowners association. Check the expiration dates; the neighborhood's no-fence rule may end in 2012.
Every region has quirky rules of its own too. In Chicago, a lot's development may be delayed because it is tagged by the Chicago Historic Resources Survey as possibly historically significant. Or the lot's soil conditions are problematic because it consists of Chicago Fire debris.
Beyond boundaries. Before you fall in love with a lot, look at the big picture.
"Sometimes, the best or worst things about a lot are not on the lot," noted Pickell. Is the adjacent property zoned commercial? Are property taxes lower in the next county? How is the school district rated?
"You have to love the approach to the property because you can't change what's beyond the surveyor's pins," said Pickell.
To learn about neighborhood nuisances, visit the lot at different times. That school next door is quiet during your Saturday afternoon visit, for example, but may have an outdoor bell set to ring at 7 a.m. every weekday.
Bottom line. "Do as much homework as humanly possible," advised Jernigan. "Then be nice to your county building department; don't make them your adversaries. Ours made the process easier because they gave us a checklist of things we had to do before we could get a building permit."
In the end, Jernigan said, building on her own lot was worth it.
"It took such a long time to find what we wanted and then deal with the delays, that I say I got an acre for every year I waited," she said. "But in the end, it's really gratifying."