Remember to go through each page and update every link which might still statically be set to the IP-address. Haven’t looked through the site, but just saw the Call Now on the front page.

Next step would be to have a look at Let’s Encrypt, but finish up the site currently - and take a snapshot before making that step, so you always can revert in case of it not working:
https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-16-04

@theisevan Didn’t notice the extra line, since you added it after with an edit.

You can edit the file called .htaccess in the WordPress root folder and add this to the top of the file:

# BEGIN Redirect non-www to www
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule ^(.*)$ http://www.evansdetailing.com/$1 [R=301,L]
</IfModule>
# END Redirect non-www to www