You need to subscribe to SM Pro to use it. If you have a Premium store, then there is no monthly charge for SM Pro. Upgrading to a Premium store does not automatically subscribe you to SM Pro.
Listing designer is an option in the eBay Online Sell Your Item form. It is under the description and you just check off Listing Designer, then select the design you want to use. There is a Preview option there to see how the design looks.
It costs 10 cents a listing to use Listing Designer. If you have SM Pro, Listing designer is Free.
If you wish to upgrade to a Premium store, usually you should only do this if you have over 227 fixed price listings a month. You currently have 140 listing in a basic store. So it will be more expensive to list as a Premium store.
The cost of 140 listings in a basic store is $15.99 + (140*$.20 =$28.00) = $43.99.
The cost of 140 listings in a Premium store is $49.99 + (140*$0.05=$7.00) = $56.99.
The difference is $13 for the Premium store but you get the SM Pro and the Listing Designer for free which is worth $15.95+. So if you really want to use SM Pro and listing designer, then upgrading to a Premium store is worth it.
I just wanted to point out the break points for a Premium store over a basic store.
Once you have a Premium store, insertion fees for listings are 5 cents so add more listings if you can if it will help increase sales.
