Changing the author of a post can come in handy when multiple users are onboard but you want it to be posted with the realtor's name, not the writer's.
To do this, find your way to the "Posts" section of your Wordpress blog on the left hand side of your page.
Once there, find "Screen Options" on the top right hand corner, above the "Publish" box.
When you click on "Screen Options" a drop down menu, like the image below, will appear. Select the "Author" box.
Scroll down to your posts, hover over the one you want to change, and click on the "Quick Edit" that will appear underneath.
From here, you can click on "Author" to open the drop down menu and choose the user you would like to use as the author for this post. Don't forget to save you modifications by clicking on "Update" in the bottom-right corner !