Quantity   Component name
1 × raspberry pi 3 / BeagleBone a SBC with HDMI output
1 × retro phone handset preferably USB because RPI sound output is bad
1 × HDMI screen size will depend on door frame'size
1 × door + frame probably from IKEA
1 × webcam generic one
1 × HAL sensor
1 × vibrator https://www.adafruit.com/product/1201 or similar