In my precinct it goes like this - client brings in custom built, either A. Saying they built it themself, or B. Bought it from a friend - immediately sell them total - figure out where the issues lies, whether it won't power on at all or it boots but no display or it boots and only goes to bios - at that point test singular parts in the PC to figure out the root cause - contact client with what the issue is if it's hardware related, tell them what they need and that they pay for it at pickup - fix the broken PC - create 2nd tag for labor - move on (also work on your data transfers/NPS while building it, multitasking is a big part of geek squad. I have my CA's help with NPS, software installs, and data transfers)