Answer to "Can the RAM on these computers be upgraded?"Yes, but take it a shop that’s done it before. 64GB of DDR4 RAM can be purchased here: https://eshop.macsales.com/item/OWC/DID2... But the hard part is getting to the memory. Apple might have considered this when they designed the layout. It should cost you about $300-$350 in labor + $350 for 64GB of memory. Good luck!