If I understand your question, that info is already on the build screen

After you select the assembly item to build, the detail area show the items in the assembly BOM

below that listing is a statement telling you how many you can build based on the on hand qty of each […]

Resolution for 'Assembly screen issue: 'In the Build Assembly screen, can you include “Qty on Hand” in the printout? Can you also allow this report to be downloaded to excel?' available: Yes.

The Assembly screen issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the Assembly screen issue yourself by looking for a resolution described in the article. If it is a complex Assembly screen issue or you are unable to solve the issue, you may contact us by clicking here or by using other Assembly screen support options.

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