I took my S5 in to have a broken screen replaced. He replaced it in about about an hour and I immediately noticed that the home button was not functioning properly. It no longer clicked when I pressed it. I was willing to live with this since it still worked. There was also a foul smelling liquid oozing out of the edges of the phone and the in back behind the batter cover. He said that this was normal and would go away over time. On the way home from the shop the screen turned off. I had to pull the battery multiple times for it to work, but it still keeps shutting off intermittently.
When I took the phone back to him, he said he could replace the glass again, but it is likely that a fluid he used in the process touched the back of the LCD panel which is causing a short. He then offered to sell me a whole new LCD panel to fix this problem (an additional $100). I don't see why I should pay for additional damage that he caused.
Bottom line: I took my working phone in for a cracked screen, he broke my phone and wants me to buy more components to fix the damage he caused.