1999 Nissan Sentra 2.0 non abs this vehicle is one of my friends he's not automotive inclined whatsoever and has been taken advantage of this car is had 3 master cylinders and 3 brake jobs done by Les Schwab and other shops I recently changed all the brakes and master cylinder for him bled and bench bled and still have a spongy pedal . By all means I am NOT a Master Tech but brakes are pretty easy but I am stumped and need help

You could try and get new brake lines.
Another reason for the spongy feeling could be a small leak where air is getting in.

Try bleeding at the master. Sometimes the air just won't make it all the way to the wheels.