I was a Mac Genius for 7 years. Fact is, if you're not regularly repairing these devices daily and fully know their tolerances/peculiarities (and each phone has little tricks and "gotchas" as time goes on you learn them), most common folks don't have the dexterity, finesse, patience and nimble fingers to handle most component-level iPhone repairs. There's all sorts of annoying glue and fasteners that are unfamiliar to most people, ZIF/LIF connectors, non-magnetized screws, heat shields and display calibrations that need to be done.
Mac notebooks were tight quarters enough, iPhones are another magnitude beyond it.
The catch is Apple will see a ham-fisted repair, and charge out-of-warranty prices to remedy the damage or deny service entirely.
If you don't know what GSX and a spudger is... this is a trap.