Grouped product for telecommunication shop

Hi,
I have a question how to configure a scenario, that is mainly used by  telecommunication shops:
There is a smartphone, with different options (i.e. different color, different RAM, different memory). For this smartphone there are optional different contracts, and one has to be selected together with the smartphone.  Also the related contracts with different specifications have to be displayed side by side below the smartphone
I tried with grouped products, but in this case, it is not possible to configure attributes in the main grouped product.  I cannot find an other option to configure this scenario. In my opinion it is not a rare scenario, and maybe some customers from telecommunication business will use NopCommerce. Thanks in advance for your support!

It may be doable with conditional attributes.
See this post (and watch the video)
https://www.nopcommerce.com/en/boards/topic/46242/screencast-overview-of-conditional-product-attributes
Although it says that you can't control the values that are shown in another attribute, what you might be able to do is have several other attributes having just one other attribute (your contract/plan) appear or not.