Installing a Waveshare 7 inch Capacitive Touch Screen LCD 1024×600 HDMI interface For Raspberry Pi/BB BLACK/PC/Various Systems
The 7 inch Capacitive Touch Screen LCD 1024×600 HDMI interface For Raspberry Pi/BB BLACK/PC/Various Systems sold on Amazon by Unipro Tek is a Waveshare 7 inch HDMI LCD (C).
There is an installation Wiki on Waveshares site. While using another monitor, follow this install script for Raspian Jessie. Section
(How to configure original Raspian Image file) if you do not want to destroy your existing install.
Just copy the driver, for me RPI_2B_USB_TOUCH_CAP_RASPBIAN-3.18.16-v7-7.0-1024×600-20150910.tar for Raspberry Pi 2 Model B on your pi and
sudo tar zxvf file_name.tar.gz
or however it is called.
Then shutdown the Pi, plug in the LCD and the Mini USB from the Pi as Power source for the LCD monitor an you are done,
If you have power issues, the site advises to use.