11. Add HDMI
Rather than having an HDMI port, the EliteBook came with a DisplayPort video connector. DisplayPort works well with my monitor in the office, but when I travel, I have to connect a projector using the system's VGA port, which doesn't handle audio. It's an easy fix with a DisplayPort-to-HDMI adapter, which averages about $10 to $20.
If you don't have a DisplayPort connector, look for a VGA-to-HDMI adapter, which should cost about $25 to $30.