QBO does not have unit of measure, so you have to stock an item in the lowest unit you sell at

from what you say you need two different inventory items, beads-strung and beads-loose

for each 1/2k bag you buy, you enter the qty as a multiple of how you sell it, […]

Resolution for 'bulk item issue: 'How to list inventory for bulk item which is also broken down into smaller units?' available: Yes.

The bulk item 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 bulk item issue yourself by looking for a resolution described in the article. If it is a complex bulk item issue or you are unable to solve the issue, you may contact us by clicking here or by using other bulk item support options.

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