1. Never disconnect any cable inside the iPhone before te iPhone is turned off and the battery is disconnected.

2. If your iPhone can't find any network after repairing, then check if the date and hour is correct! If not, do that and restart your iPhone.

3. If your iPhone is in DFU mode then don't reset it, but try to get it out of DFU mode with PhoneResceu. (Mostly you also have your files back)

4. Every Error code that iTunes give u after trying to reset your iPhone has a meaning witch you can see on the apple site. (https://support.apple.com/en-us/HT204770)

5. Always place your screws in the same order as you screw them out of your iPhone, because every screw has a special function! (Some screw are used to connect your antenne to your iPhone case)

6. If u place an new screen assembly on an iPhone, then be sure that your flex cables of your screen does not remain pinching between the metal frame and the screen. (especially for the iPhone 4 and 4s)

7. It's really important to take your time for repairing an iPhone.

I've Ordered for more then 2 years by ETrade Supply and i have never got any problem with them! 

Thanks for my account manager and all the rest of the guys over there!

Regards from Belgium!

Brent

(Sorry for my English)