OT: system recommendation

[Mike Bonner]

Sorry for the off topic question, but this is my most trusted place for
tech knowledge.  Appreciate any tips and advice (for a friend).

My friend is looking to buy or build a pc to do 4k video editing.  I know
the obvious part.. If you can afford more memory, add more memory.

After that, I'm lost.  intel vs amd?  For video, amd or nvidia or something
else?  Is there a synergy between choice of motherboard/cpu make/video
choice?  As for hard drive setup, i'm thinking a 500g ssd boot device and a
single 7200rpm 3tb or greater drive (drive space is CHEAP!)

I also don't know how important drive throughput is for vid processing.  I
know it matters, but how fast is fast enough?  Does it pay to set up a
striped set of 3 or 5 drives?  Or a hybrid drive?

Is it acceptable to do the processing on a non 4k monitor?

Unfortunately, cost IS a factor.  I know it boils down to how much cash one
wants to throw at it, but i'm looking for best bang for the buck, 1500 or
less.  (things could be bumped up later by adding mem, better monitor to
view output.

Oh, also, this will not be online editing (Which I assume to mean "live")
and will be video from a gopro so the bitrate won't be as intensive as say
a RED quality camera.

Thanks for any and all suggestions, and helping me provide better
recommendations to my friend.