hardware

Greetings, Recently I bought from ebay an Inspire1 used ofcourse. What are most important things to check, so in case any issues would like to detect them in first day, not after 1 month from buying it. I could benefit from eBay sellers protection and get my money back if there are something...

I am interested in knowing what you think is minimum, maximum, useful, useless hardware for editing 4K video. I have a PC 16gb ram, Internal 7200 rpm hd, USB 3 external 2 tb drives, I7 processor, desktop, 27" RGB monitor, good video card w 2 mb ram not a $59 nor a $1,200 card but some where in...