Setting up a WP site under a test environment before transferring to new URL

Hi there,

I’m sure this question has already been asked but searching the forums have come up dry for me (perhaps I’m just not searching using correct terminology).

Anyway, my question is regarding the process of setting up a WordPress site for a client who already has a non-Wordpress website running. I want to set up and design a WordPress site using a theme, along with some widgets and images (in the media library). I have no issues setting the site up under a test domain, but then, all the url that are referenced, along with all of the images that I uploaded, are all under the testdomain.com. Once the site design is approved, what is the easiest way to move the site to the new URL, without having to go and change every single link and image on my site to the new URL? Does that make sense? Hopefully it does, and hopefully there is a simple, straightforward answer.

Thanks in advance for any suggestions!!

D.