Nowadays, if you build a desktop, you get 6 slot of RAM.
If you buy a laptop, you get 1 slot, and have to buy a single expensive 32gb ram to replace the old one. If you unlucky enough, you can have onboard RAM with no way to upgrade.
Yeah dudes. That is how apple work.
And my Lenovo only have 1 slot of 16gb Ram, to get 32 gb RAM i got to buy it at Lenovo center because it is so rare no repair shop or store have it on hand.