My first post on this site! Thought you may be interested in my $25 Backup Camera Installation on my 2012 Camry XLE.
I think you will find it interesting and informative. It is done in a step by step tutorial with pictures of the steps from start to finish of the install.
I bought my backup camera kit on eBay for $25, it was all that I needed to do the installation.
Here is the link to the Tutorial: http://www.mrrace.com/BUCamera/
Enjoy,
George