Purchase a car that has a AVN-W4400Nex  - i see that you can purchase replacement screens - but i don't know how to get the face plate off since  the digitzer doesn't recognize when i touch the screen. I screen comes up clear and looks like it would function. Took it to car toys and they said i needed to replace the radio. Any thoughts before i go down that route ?  

This is just my opinion but the bottom of the screen comes out and the top drops down. I would try to pry out the bottom, carefully, and push down the top. Granted I have never done this but I don’t remember it “latching” when it closes. Then then if it comes out there is a little slider latch, I think it is on the right side, that you move to remove the faceplate from the holding track. Sorry I am currently in my wife car and don’t have access to my unit right. I mean shucks what do you have to lose by trying. Just my opinion.