If you suddenly want to flash the BIOS in your mini-pc, then I highly recommend that you first watch this video and buy a programmer.
https://github.com/bootuz-dinamon/GK3V-minipc - all BIOS versions for GK3v are collected here.
http://alii.pub/6ge0dm - ch341a programmer
Mini pc with good reviews for smart home server:
https://ali.ski/G_J4I - mini PC GK3V on Celeron j4125 or n5105
https://ali.ski/haYHbv - Beelink GK Mini on Celeron j4125 and n5105
https://ali.ski/cfk_8 - Beelink U59 Mini Celeron n5095
https://ali.ski/veBXs- - Mele j4125 fanless mini pc
https://ali.ski/1g5c_ - fanless XCY j4125
https://ali.ski/sGKI1T - fanless SZBOX Celeron n6005
https://ali.ski/KptbA - fanless i5-8265U
https://ali.ski/yF81vW - fanless n5105 with 4 2.5 Gb LAN ports!!!!
And this might come in handy too:
http://alii.pub/6ge0r8 - Orico USB 3.0 hub
http://alii.pub/6ge2lc - keyboard and mouse 2.4 GHz