“This house is on two acres.” Disputes about property dimensions – how many square feet in a house or condo, or its exact boundaries – are common. Sometimes buyers don’t learn the exact dimensions until the lender’s appraisal.

“We Don’t Have Pests.” A basic home inspection generally doesn’t include a peek inside walls or underground for termites and mold, which are among the top complaints. Inspections for mold and radon gas also generally aren’t included; usually buyers must order these inspections separately. Other inside-the-wall problems include faulty wiring and old plumbing, which also may require specialists.

“This Place Never Floods.” Even arid states such as Arizona and New Mexico have occasional flash floods, and water and drainage problems aren’t always obvious. June Walbert, 52, a certified financial planner at USAA, a financial-services company, says her San Antonio house received a clean bill of health from a home inspector before she bought it six years ago. But 10 days after she moved in, the sewer backed up, flooding the house, and she had to fork over $2,800 for repairs. “It was a rude surprise,” says Ms. Walbert, who adds she asked her home inspector and the seller for compensation, but didn’t get it.