Buying a used iPhone can save you hundreds of dollars—the iPhone 15 Pro that cost $999 new is now available for $650-750 used. But with savings come risks: iCloud locks, undisclosed water damage, degraded batteries, and non-original parts can turn a great deal into an expensive mistake.
This comprehensive 2026 guide covers every test you need to perform before handing over cash. Whether you're meeting a private seller, buying from a reseller, or evaluating a refurbished unit, these 50+ checkpoints will reveal any hidden problems and help you negotiate a fair price.
2026 Update: This guide covers iPhone 12 through iPhone 16 series, including Pro, Pro Max, and Plus models. It includes checks for Apple's new Repair State, parts pairing verification, and iOS 18+ specific diagnostics.
Before Meeting the Seller
Do your homework before you travel to inspect the phone. These remote verification steps can save you from wasted trips and potential scams.
Essential Pre-Meeting Requests
1. Request IMEI/Serial Number
Ask the seller for the IMEI (dial *#06#) or serial number. Then verify:
- • Apple Coverage Check:
checkcoverage.apple.com- Shows warranty status, model, and AppleCare eligibility - • Activation Lock Status: If Activation Lock is ON, the seller must be present to remove it
- • Carrier Lock: Ask seller to check Settings → General → About → Carrier Lock
2. Request Battery Health Screenshot
Ask for a screenshot of Settings → Battery → Battery Health & Charging showing:
- • Maximum Capacity percentage
- • Peak Performance Capability status
- • Cycle Count (iOS 17.4+)
- • "Genuine Apple Part" indicator
3. Verify Listing Details
Cross-check claimed storage/color with Apple's coverage check. Scammers often:
- • Advertise higher storage than actual
- • Use stock photos instead of actual device
- • Claim "unlocked" for carrier-locked phones
🚫 Walk Away Immediately If:
- • Seller refuses to provide IMEI/serial before meeting
- • IMEI comes back as stolen/lost on carrier databases
- • Seller insists on shipping instead of local meeting
- • Price is significantly below market value (likely scam)
- • Seller claims they can't unlock it but "the buyer can easily do it"
Physical Inspection
A thorough physical inspection reveals drops, water damage, and non-original parts. Bring a flashlight and inspect the phone in good lighting—many defects are invisible under dim conditions.
Exterior Inspection Checklist
Display Glass
- • Check for cracks or chips at all angles
- • Look for micro-scratches under bright light
- • Verify oleophobic coating isn't worn
- • Check corners for impact damage
Back Glass
- • Inspect for cracks (common drop point)
- • Check camera bump area for damage
- • Look for scratches or scuffs
- • Verify color matches advertised
Frame & Buttons
- • Check all corners for dents/dings
- • Test Volume Up, Down, Action Button
- • Verify Side Button responsiveness
- • Check SIM tray for damage
Ports & Openings
- • Inspect USB-C/Lightning for debris
- • Check speaker grills for blockage
- • Verify SIM tray seats properly
- • Look for signs of prying/opening
Water Damage Indicators (LCI)
iPhones have Liquid Contact Indicators (LCI) that turn red when exposed to water. Check these locations:
SIM Card Tray Slot:
Remove SIM tray, shine flashlight into slot. White/silver = good. Red/pink = water damage.
Other Signs:
- • Corrosion around charging port
- • Fog under camera lenses
- • Discoloration around speakers
Screen Replacement Detection
Non-original screens often have subtle tells:
- • Uneven bezel gaps: Third-party screens often don't seat as precisely as OEM
- • Color temperature mismatch: Compare screen white to Apple Store display models
- • True Tone disabled: Settings → Display → True Tone grayed out indicates non-original display
- • Parts and Service History: Settings → General → About shows "Unknown Part" for non-genuine displays
Battery Health Testing
Battery degradation is the most common issue with used iPhones. Apple's battery health tools provide detailed information, but you need to know what the numbers mean and how to verify them.
Understanding Battery Health Metrics
| Maximum Capacity | Condition | Recommendation |
|---|---|---|
| 90-100% | Excellent | Full price justified |
| 85-89% | Good | Minor price reduction |
| 80-84% | Fair | Negotiate $50-75 off |
| 70-79% | Poor | Needs replacement ($99-169) |
| <70% | Critical | Immediate replacement needed |
Battery Health Verification Steps
Check Official Battery Health
Settings → Battery → Battery Health & Charging. Note Maximum Capacity and Peak Performance status.
Check Cycle Count (iOS 17.4+)
Settings → General → About → scroll to "Cycle Count". Under 500 cycles is good; over 1000 indicates heavy use.
Verify Genuine Battery
Settings → General → About. If battery says "Unknown Part" it's been replaced with non-Apple part.
Real-World Drain Test
If possible, use the phone for 15-20 minutes with screen on (watch YouTube, browse web). Battery should drain linearly, not in sudden jumps.
💡 Battery Replacement Cost Reference (2026)
iPhone 16 Series: $119
iPhone 15 Series: $99
iPhone 14 Series: $99
iPhone 13 Series: $89
iPhone 12 Series: $89
Pro Max models: +$30-50
Display Testing
OLED displays can develop burn-in, dead pixels, and touch responsiveness issues. These problems may not be immediately obvious but significantly impact daily use.
Display Quality Tests
Dead Pixel Test
- Open Photos app, create solid color images
- View full-screen: pure red, green, blue, white, black
- Look for any pixels that don't match
- Check all corners and edges carefully
OLED Burn-In Test
- Display solid gray at 50% brightness
- Look for faint image retention
- Check keyboard area, status bar, home bar
- Tilt screen to different angles
Touch Response Test
- Open Notes, draw on entire screen area
- Check for dead spots or missed touches
- Test all four corners thoroughly
- Try drawing continuous diagonal lines
3D Touch / Haptic Touch
- Long-press app icons for context menu
- Test across different screen areas
- Verify flashlight/camera lock screen shortcuts
- Check haptic feedback during press
ProMotion & Display Features (Pro Models)
For iPhone 13 Pro and newer Pro models, verify these features:
- ProMotion (120Hz): Scroll through long web pages or lists—motion should be noticeably smoother than 60Hz phones
- Always-On Display (14 Pro+): Lock the phone and verify the dimmed lock screen appears with time/widgets
- True Tone: Settings → Display → True Tone should be toggleable (grayed out = non-original display)
- Night Shift: Test color temperature adjustment works smoothly
Face ID & Touch ID Testing
Biometric authentication is critical for security and convenience. Damage to Face ID sensors or Touch ID buttons often isn't repairable, making thorough testing essential.
Face ID Testing (iPhone X and newer)
Basic Setup Test
Ask the seller to reset Face ID (Settings → Face ID & Passcode → Reset Face ID), then set up YOUR face. This verifies the TrueDepth camera system works and isn't locked to previous owner.
Reliability Test
After setup, test Face ID 10+ times from various angles: straight on, slight angles, with sunglasses (if supported), in different lighting. Should work 9/10 times or better.
Feature Verification
Test Face ID for: device unlock, App Store purchases, password autofill, third-party app authentication (banking apps if you have one installed).
Touch ID Testing (iPhone SE, older models)
Fingerprint Enrollment
Reset existing fingerprints and enroll your own. The enrollment process should complete smoothly without repeated "lift finger" errors.
Button Feel
The Home button should have consistent click feel. A mushy or stuck button indicates wear or water damage that may worsen over time.
⚠️ Critical Warning
If Face ID or Touch ID doesn't work and shows "Unable to activate" in Settings, the biometric hardware has likely been replaced with non-genuine parts. This is NOT fixable except by Apple, and they may refuse service. Walk away from these units unless priced accordingly ($150-200+ discount).
Camera System Testing
Modern iPhones have sophisticated multi-camera systems. Each lens, optical stabilization system, and software feature needs individual testing to ensure full functionality.
Camera Test Checklist by Lens
Main (Wide) Camera
- ☐ Photo focus speed (tap to focus)
- ☐ OIS test (record video while walking)
- ☐ Low light performance
- ☐ Night mode activation
- ☐ Portrait mode blur quality
- ☐ 4K 60fps video recording
- ☐ Slow-mo recording
- ☐ No dust/debris on sensor
Ultra Wide Camera
- ☐ 0.5x zoom switches smoothly
- ☐ Edge distortion acceptable
- ☐ Macro mode (iPhone 13 Pro+)
- ☐ No vignetting or dark corners
- ☐ Color matches main camera
- ☐ Video recording works
Telephoto Camera (Pro Models)
- ☐ Optical zoom engages (2x/3x/5x)
- ☐ Focus at various distances
- ☐ Portrait mode at telephoto
- ☐ OIS stabilization working
- ☐ Low light performance
- ☐ No stuck/dead pixels in output
Front (TrueDepth) Camera
- ☐ Selfie photo quality
- ☐ Portrait mode / Depth Effect
- ☐ FaceTime video quality
- ☐ Center Stage (iPhone 16+)
- ☐ Animoji/Memoji tracking
- ☐ No dust behind glass
Special Camera Features to Test
Cinematic Mode
Rack focus in video
ProRAW
48MP capture (Pro)
Action Mode
Heavy stabilization
Cellular & WiFi Testing
Connectivity issues can render a phone nearly useless. Testing cellular, WiFi, and Bluetooth ensures the phone's radios are fully functional.
Cellular Network Tests
SIM Card / eSIM Test
- • Insert your SIM card and verify it's recognized
- • For US iPhone 14+: Test eSIM activation capability
- • Check signal strength in Field Test mode (*3001#12345#*)
- • Verify LTE/5G indicator appears
Carrier Lock Status
- • Settings → General → About → Carrier Lock
- • "No SIM restrictions" = Unlocked
- • If locked, verify it's to YOUR carrier or get unlock commitment
Call & Data Test
- • Make an outgoing phone call (test earpiece speaker)
- • Receive an incoming call (test ringer)
- • Turn off WiFi, load a webpage over cellular
- • Send and receive an SMS/iMessage
WiFi & Bluetooth Tests
WiFi Testing
- • Connect to 2.4GHz and 5GHz networks
- • Run speed test (fast.com or Speedtest)
- • Verify WiFi 6/6E (iPhone 11+)
- • Test AirDrop send/receive
- • Walk to edge of WiFi range
Bluetooth Testing
- • Pair with headphones/speaker
- • Test AirPods if available
- • Verify Apple Watch pairing capability
- • Test handoff between devices
- • Check Bluetooth stays connected
Audio & Haptic Feedback Testing
iPhones have multiple speakers and microphones, plus a sophisticated haptic engine. Testing each component individually reveals issues that aren't obvious in casual use.
Speaker & Microphone Tests
Stereo Speaker Test
Play music and verify:
- • Both top and bottom speakers produce sound
- • No rattling, buzzing, or distortion at max volume
- • Balance between speakers is even
- • Spatial Audio works (compatible content)
Earpiece Speaker Test
Make a phone call and verify:
- • Clear audio through earpiece
- • Volume adjustment works
- • No crackling or static
Microphone Tests
Test all microphones using Voice Memos:
- • Bottom mic: Record with phone flat on table
- • Front mic: Record while holding phone to ear position
- • Rear mic: Record video and check audio clarity
- • Test Siri voice recognition
Taptic Engine (Haptics) Test
The Taptic Engine provides haptic feedback. Test these scenarios:
- • Typing: Enable keyboard haptics (Settings → Sounds & Haptics → Keyboard Feedback)
- • 3D Touch/Haptic Touch: Long-press icons on home screen
- • System Haptics: Toggle switches in Settings should produce subtle taps
- • Ringtone: Set phone to vibrate, receive a call
⚠️ Weak or absent haptics often indicate water damage to the Taptic Engine
Software & Security Checks
Software verification ensures the phone isn't stolen, iCloud locked, or running modified firmware. These checks protect you from buying a phone that might become a brick.
Critical Security Checks
🔒 Activation Lock Verification
This is the MOST important check. An Activation Locked phone is worthless to you.
- Ask seller to sign out of iCloud (Settings → [Name] → Sign Out)
- Erase the phone (Settings → General → Transfer or Reset → Erase All)
- Go through setup until you reach the Home screen WITHOUT entering their Apple ID
- If setup asks for previous owner's password, the phone is LOCKED. Walk away.
Find My iPhone Status
Verify Find My is disabled: Settings → [Name] → Find My → Find My iPhone should be OFF. If seller can't disable it, they may not be the legitimate owner.
Repair State Check (iOS 17.5+)
Apple introduced "Repair State" to prevent stolen phones from being wiped. If the phone shows "Repair State" or asks for original owner credentials during setup, it may be stolen.
Parts & Service History
Go to Settings → General → About and check for parts verification messages:
Software Version Check
Check Settings → General → About → iOS Version. Verify the phone:
- • Can update to latest iOS version (not blocked by MDM or jailbreak)
- • Isn't running extremely old iOS (may indicate avoided updates due to issues)
- • Shows no unusual profiles (Settings → General → VPN & Device Management)
Master Testing Checklist
Use this interactive checklist during your inspection. Any failed items should factor into your purchase decision and negotiation.
Pre-Meeting Verification
Physical Condition
Display & Touch
Face ID / Touch ID
Camera System
Connectivity
Audio & Haptics
Software & Security (CRITICAL)
2026 Used iPhone Pricing Guide
Use these reference prices to evaluate deals. Prices assume excellent condition (90%+ battery, no damage, unlocked). Adjust down for issues discovered during testing.
| Model | 128GB | 256GB | 512GB+ | Notes |
|---|---|---|---|---|
| iPhone 16 Pro Max | $950-1050 | $1000-1100 | $1100-1250 | Latest gen, minimal savings |
| iPhone 16 Pro | $800-900 | $850-950 | $950-1050 | Best value current Pro |
| iPhone 16 | $600-700 | $650-750 | $700-800 | Action Button, USB-C |
| iPhone 15 Pro Max | $750-850 | $800-900 | $900-1000 | 5x telephoto, great value |
| iPhone 15 Pro | $650-750 | $700-800 | $800-900 | Sweet spot for Pro features |
| iPhone 15 | $500-600 | $550-650 | $600-700 | First USB-C standard iPhone |
| iPhone 14 Pro Max | $550-650 | $600-700 | $700-800 | 48MP camera, Dynamic Island |
| iPhone 14 Pro | $475-575 | $525-625 | $625-725 | Budget Pro option |
| iPhone 14 | $375-450 | $425-500 | $475-550 | Lightning port (last gen) |
| iPhone 13 Pro | $375-450 | $425-500 | $500-600 | First ProMotion iPhone |
| iPhone 13 | $300-375 | $350-425 | $400-475 | Best budget option |
| iPhone SE (3rd gen) | $200-275 | $250-325 | — | Touch ID, A15 chip |
Price Adjustment Guide
Deduct From Price:
- • Battery <85%: -$50 to -$100
- • Non-genuine parts: -$75 to -$150
- • Cosmetic damage: -$25 to -$100
- • Carrier locked: -$50
- • Missing accessories: -$20 to -$50
- • Face ID disabled: -$150+
Worth Paying More:
- • AppleCare+ remaining: +$50-100
- • Original box/accessories: +$20-30
- • Battery 95%+: Fair asking price
- • Recent Apple battery replacement: +$30-50
- • Apple refurbished: Peace of mind premium
💡 Where to Buy Used iPhones
Safest Options:
- • Apple Certified Refurbished
- • Amazon Renewed Premium
- • Back Market (verified refurbishers)
Best Prices (More Risk):
- • Facebook Marketplace (local)
- • Swappa (verified IMEI)
- • eBay (buyer protection)