Duplicate content issue

[MktgPro]

I work with some real estate agents who have websites from a template-site provider. There's some concern that they are getting hit for duplicate content, and I'd really appreciate help in figuring this out.

Each website has a purchased domain name like www.mydomain.com. The pages in the site show as www.mydomain.com/pageid.html

However, when you visit an internal page, and return to the home page using the navigation links, you end up at a URL like: www.mydomain.com/homepageid.html

The HTTP header status on both domains show a Status of 200.

Can anyone tell me if Google would consider these duplicate pages? Can you form an opinion based on what I've shown? If not, what else should I look for?

Thanks for your help.

Kathleen