Alternatively, you might suggest to your client that they take this out of the context of D365 Sales and consider deal with it in an ERP that offers, at least, basic BoM (Bill of Materials) capabilities, as that is exactly what you described. D365 Business Central can do this. Typically, BoM is associated with manufacturing, but there are many cases out there of companies that don't truly 'manufacture' something; rather they do 'kit assembly'. But the software capabilities are the same at that level, its just that the levels below that such as routings and engineering control and so on aren't required. The "final product" in your description is what is made available to D365 Sales to sell. The huge advantage of this is that they get all the costing, including WIP (Work in Progress), and the associated financial system postings as part of the deal. Which they will NOT get through your custom approach in D365 Sales.
There are, of course, less costly alternatives to Business Central. MANY. But what you're describing really does belong in the ERP realm not the 'CRM' realm. And doing it properly in an ERP system that provides BoM capability doesn't rob you of revenue as they will still need some custom dev work done to integrate a non-Dynamics ERP to D365 Sales.
Oh, and this is the first time I've heard anyone call it "Powerflow", LOL!
