Hi @mandyt93,
Answers to your questions inline below.
I want to redesign the advance search and make it part of the header so its visible on every page. http://www.impacttfs.com.au
The advanced search page can be added anywhere on your site using the shortcode [businessdirectory-search]. As for “redesigning” it–we don’t have settings for that except for the order of the fields on the form. We have several options for customizing the look of the directory. For the search form, we have instructions on how to customize anything in the plugin if you have the proper skill set: http://docs.businessdirectoryplugin.com/themes/customization.html
It will require advanced HTML, PHP and WordPress API skills to do and once you make those changes, upgrades to the plugin will be more challenging as you have to migrate your changes to those later versions yourself.
Secondly, I want to add a list of suburbs so customer could select one from the drop down.
This is part of the Regions module if you want to filter listings based on this location data. You can purchase that here: http://businessdirectoryplugin.com/premium-modules/
Or you can just add a field under Directory Admin->Manage Form Fields, if you don’t want filtering.
Third, is it possible that everytime we open http://www.impacttfs.com.au/member-benefit, get to the same page as http://impacttfs.com.au/member-benefit/?wpbdp_view=all_listings ?
Yes, you can use a 301 redirect in your .htaccess file to direct users to that URL from the previous one. Or use a plugin like Page Links To (by Mark Jaquith) that allows you to take a page and redirect traffic that way (much easier).
Please let me know if you have any further questions!