Start with the basics: verify the device’s physical condition, battery health, and that it powers on without issues. Check the screen for scratches or dead pixels, the camera lenses for clarity, and test all buttons and the charging port. Ensure the iPhone isn’t locked to a previous owner and that it can be reset to factory settings. Confirm the handset includes essential accessories or a reasonable explanation if something is missing, and assess the seller’s return policy.

Look for signs of battery swelling, water exposure, or screen inconsistencies like uneven backlighting. Notice any unexpected heating during use, rapid battery drain, or frequent unexpected restarts. Examine the camera for blurry or misaligned images and listen for abnormal speaker or microphone behavior. These indicators may reveal underlying problems that aren’t immediately visible in photos or basic demonstrations.

Ask about the device’s history, prior repairs, and whether it’s iCloud/Apple ID-free and unlocked. In-person checks should include turning on the phone, checking the battery health, scanning for iCloud lock status, and confirming the device responds to touch accurately. Bring a charger to verify charging speed, and test the SIM tray in case of carrier lock concerns. Request proof of purchase if possible and a short-term return option.

Confirm the device is unlocked or compatible with your carrier’s network bands. Check the iOS version and whether it’s eligible for the latest updates, as this affects security and features. If you rely on eSIM, ensure the phone supports it with your carrier. A clean IMEI check can also confirm eligibility and avoid blacklists. These steps help ensure ongoing software support and service coverage.

Compare prices against current market resale values for similar devices in your region, considering condition and included accessories. Look for any seller warranty or return policy; a short, reasonable warranty provides peace of mind for cosmetic or functional issues. Avoid prices that seem unusually low, which could indicate hidden problems. A documented return window helps you test the device after purchase and protect your investment.

Request the original box, charger and cable if possible, along with any recent service records or repairs. A certificate of purchase or proof of ownership can help establish authenticity. If available, include accessories like a case or screen protector that was used with the device. Clear documentation reduces questions about legitimacy and helps ensure you receive a complete setup kit.