If you have single property websites for listings you should feature them on your website. Take a look at www.markrogo.com and click on listings to see that each listing is featured by address and links right to the property website.
You'll also see how the Rogo's have added a voice message to their website directing visitors to see the property websites.
Adding audio to your website gives it a personality and helps keep visitors on your site. Audio is another free feature that is included with all eProspecting websites.