Passage Summary: Buying used gym equipment from a fitness center is a good idea because the machines are built to last and are kept in good shape, despite being used often.

Conclusion: Fitness centers can be excellent locations to purchase pre-owned exercise equipment.

Reasoning: Gyms sell their old equipment at fair prices when they upgrade, and these machines are typically higher quality and better maintained than home models.

Analysis: The argument provides several premises—reasonable price, superior build quality, and good maintenance—to support a value judgment. To justify this conclusion, we need a principle that establishes these specific criteria as the standard for a 'good' purchase. Look for an answer choice that explicitly links high-quality construction and professional maintenance to the desirability of a used product, even if that product has been heavily used.