Can there be difficulties in upgrading the computer?

Question

ASUS

Good day!
I plan to buy the next configuration with the ability to grow.
motherboard Asus X99E_WS which has a maximum of 128 GB and 4 vidyuhi and stones can stand i7 and xenon.
First put on it:
64GB RAM
1 video card NVIDIA 1080 or Titan pascal
i7 is not very expensive
then save and increase RAM, number of video cards and change the percentage to expensive i7 or xenon, water cooling
What problems can arise during an upgrade?
if you take vidyuhi and RAM of the same models? or if the vidyuha is updated, will I still
be able to fix the problem with firewood or?
And what offices collect and with guarantees?
Thank you!