In a previous job I fixed power supplies, pc motherboards, printers, tvs, video (that long ago!).
So many repairs just involved an ESR meter and changing electrolytics.
Same applies now but I dont have the kit to remove surface mount semis (ICs) (except for Rs and Cs).
Re-balling kits for BGA are beyond he reach of all but specialist companys now. I even had access to x-ray equipment to check BGA solder joints.
I still do repairs but nothing like my previous level. 
So many specialist ICs are not available or so expensive that repair is not economic for me know.