How to figure out if you can upgrade your MacBooks's hard drive
Upgrading the new MacBook Pro is still a major pain
MacBook Pro 13" Retina Display Early 2015 SSD Replacement - iFixit Repair Guide
NEW A1708 Laptop SSD 128GB 256GB 512GB 1TB For Macbook Pro Retina 13.3" 2016 2017 A1708 Solid State Disk EMC 3164 EMC 2978|Internal Solid State Drives| - AliExpress
Can You Upgrade the Hard Drive or SSD In Your Mac?