I had an issue with my rear windscreen when it was replaced by Windscreens OBrien..... first installed the wrong screen (WRX STi) as it did not have the radio aerial in the screen plus it blew fuses every time I tried to use the rear demister. To add insult to injury they smeared black silicone on the blue inserts on my rear seat......
The end result was 2 days of my time a $1600 genuine subaru rear screen (as the cheap crap one they installed was just that) $580 worth of rear seat trimming and twice the amount of work to replace the screen.
All this from a screen replacer with 20 years experiance, I would have opted for the apprentice if it meant that he was going to take more care and pride in his work.