Here's a pre-owned Macbook Pro 13" A1502 laptop computer that is firmware locked.  I bought it at a thrift store thinking I could erase the hard drive and use it but I can't.  So, I'm selling it for parts.  I don't know the hard drive or RAM size.  I believe the A1502's were made from 2013-15, comes with a power cord and it looks good.  It does turn on, the arrow works and I can type into the password box.  Me?  I'm not a store/Steve Jobs.  Buy accordingly.  I figured somebody with more knowledge could get it working or, at the least, use it for parts...and am selling as such.  Put it to work.  Thanks for your interest and best of luck.