Compare Pricing: Research market rates for similar hours/conditions. Prices below 30% of new may signal hidden issues.

Common Issues: For older 320/336 models, inspect the final drives and swing motors, which are prone to wear.

Aftermarket Attachments: Ensure compatibility with your attachments (e.g., buckets, breakers) to avoid retrofit costs.

Spare Parts Availability: Verify part availability for discontinued models to prevent downtime.

Fuel Efficiency: Newer engines (post-2012) meet stricter emissions standards, reducing long-term fuel costs.