There is no widely recognized saying specifically about replacing doors in second-hand homes, but related principles emphasize thorough inspection and investment in foundational elements. When purchasing a used property, professionals recommend evaluating doors for security, functionality, and energy efficiency. Replacing doors is often seen as a cost-effective upgrade, particularly if they show wear, are outdated, or lack modern safety features like deadbolts.

The importance of door replacement in second-hand homes stems from practical and financial considerations. Doors are critical for security, energy conservation, and curb appeal. According to the National Association of Realtors (NAR), 80% of homebuyers prioritize inspecting entry doors during walkthroughs, as they signal a property’s overall condition. A 2022 study by the American Society of Home Inspectors found that 15% of door-related issues in older homes—such as rot, poor insulation, or malfunctioning locks—were classified as "critical" and required immediate attention. Replacing a door can cost between $200 and $1,000, but this investment often yields long-term savings. For example, energy-efficient doors can reduce heating and cooling costs by up to 10%, according to the U.S. Department of Energy. Additionally, upgrading doors with smart锁 (smart locks) enhances security, aligning with rising buyer demands for modern features. While no proverb explicitly mandates door replacement, real estate experts consistently highlight it as a strategic step to ensure value, safety, and sustainability in second-hand properties.