Personally I'd go with DDR4 and an m.2 slot, which you can get with a 14" screen for like $200, but it may be more if a 19" screen is important.
Discussion
what model is that
Something like this, then just drop in a new Samsung 980 EVO 1TB nvme SSD (cause I never trust refurbished storage devices)
https://www.amazon.com/Dell-Latitude-Business-Certified-Refurbished/dp/B07GSGV2C8
Thanks. I have MAJOR issues with the keyboard layout on that one in particular.
✅ CTRL vs FN
❌ Backspace Key
❌ Enter Key
❌ Inverted T Arrow Keys
❌ Numeric Keypad