Every Rental Mac has no password, Please Hit Return if the mac is asking for a password to continue 

If you Sign into iCloud on iPad or iPhone Rental, please remember to sign out before returning   

Sign out on your iPhone, iPad, or iPod touch

1. Go to Settings > [your name]. 
2. Scroll down to the bottom.
3. Tap Sign Out.
4. Enter your Apple ID password and tap Turn Off.
5. Turn on the data that you want to keep a copy of on your device.
6. Tap Sign Out.
7. Tap Sign Out again to confirm that you want to sign out of iCloud.
    

   
    

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