Wordpress PHRETS MLS Integration

My agency re-built a real estate wordpress website for a client of ours, and on their previous website, which was designed by another agency, they were having their MLS listings pulled onto the website. I redesigned the website and needed a cost effective way to pull the RETs/IDX datafeed onto the new wordpress website. I found the PHRETS script, but I'm not sure how it works. Need somebody to install the script for me so I can have clients that visit the website be able to query the feed and find homes.