On our site we will be offering both New and Used (2nd hand) items.
 
We want to be able to highlight this apart from using a product category to do this as we will be allowing our merchants to POST to relevant category, but want to be able to re-enforce this for the customers.
 
Does anyone now how I can do this either on a Product, Product Type basis?
 
There may be additional fields (such as condition) for the Used items.

So I have made some progress on this.
I added a Product TYPE with a default specification of two options 'New' and "Used'
 
However when the merchant selects this Product Type when posting a product, there is no way i can see to show the available Specification Group name or the associated Values, so they can select one of these values. The My Products -> Edit or Add New pages only show the Type selection box.
 
Any help appreciated

Looks like Specification is not available for merchants. However from next version 4.2 there will be a feature to add extra tabs to individual products. Here is a sneak pick from admin panel.
 
Regards,
ViArt Team

Custom tabs! That's awesome! Will there be a limit to the amount of text that can be used in this field?

good news, will this 4.2 is free upgrade for current users of viart 4.1 or paid ?

 
As usual those who have valid Updates period will receive it for free otherwise an Updates Extension for about 6-12 months is required http://www.viart.com/updates_extension.html
 
Regards,
ViArt team