Multisite query…

We’ve created a few sites in WordPress but now have a client who would like a new site to show their full trade only product range (www.mainsite.com) but also the ability to duplicate the main site so they could create an unbranded site for themselves (www.unbrandedsite.com) and then several rebranded sites based on that for a handful of good customers who can just use a subdirectory (www.unbrandedsite.com/customer1). Is this possible in Multisite? It’s important that the content on the main site is always the same as the other sites so they only have to add new products to one site. It’s not an e-commerce site, just an online catalogue. It would only involve two domain names which they already own. Any advice would be greatly appreciated! They currently use Magento but we’d like to steer them clear if possible!