What are common 'red flags' that a home inspector might flag as serious issues?

A general home inspection evaluates the foundation, structure, roof, electrical, plumbing, and HVAC systems. The most costly red flags include structural issues (foundation cracks, sagging floors, bowing walls), water damage or mold (which can indicate ongoing leaks or drainage problems), outdated or dangerous electrical panels such as Federal Pacific Stab-Lok or original knob-and-tube wiring, and roof damage or age (roofs typically last 20 to 25 years for asphalt shingles). Issues like these can cost tens of thousands of dollars to remedy and should prompt buyers to request repairs, negotiate a price reduction, or consider walking away from the purchase.