More flexible inventory builds

The build option is too rigid with components being fixed once the build is setup. We have the need to change some components at different times, but still produce the same item. If it was done in the format similar to invoicing/billing, it would be perfect for us. Using the stock adjustment option to build is messy and time consuming.

In general we need the flexibility to also purchase a completed item and/or be able to build it ourselves, using the same part number.