In the past I have worked with these type of BOM applications. There's an application I put in the Exchange may be 5 or 10 years ago that demonstrates the concept of parts and assemblies being used recursively. In other words, you can make an assembly comprised of multiple parts, but then that assembly itself may become a subassembly, or like a part to something further up the chain.
Because the assemblies are related to themselves there was a limitation, I found, on how Quickbase would calculate summary totals, because in theory, there could be an infinite number of levels, and the summary fields only went up one level. So I designed the app with webhooks, which would copy that summary total across to a scalar (data entry) type field five times. But that could be changed to running the webhook say 10 times to support a BOM 10 level steep.
The name of the app in the exchange is called Assembly Costing. It might be a starting point for discussion and you could email me directly via the email address in my signature line.
------------------------------
Mark Shnier (Your Quickbase Coach)
mark.shnier@gmail.com
------------------------------