I attached a sample demonstrating similar scenario. The main problem in your case is that Hardware and Software probably doesn`t share common predecessor class. If these classes come from the database, you can create a viewmodel classes that wrap them and a base class that they will inherit from.
This way you will be able to place (for instance) Hardware and Software on one and the same tree level. Furthermore, you will be able to use different templates for these two which could be achieved by TemplateSelectors. You can find this approach in the attached solution. Please let me know if you need more info on this.
All the best,
the Telerik team
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