At present, any estimate or charge item with a minimum quantity can be deleted, with a warning.
Provide a Minimum Quantity Override option on the practice that specifies the type of user that can:
delete estimate or charge items that have a minimum quantity
change the quantity below the minimum quantity
If a user has Minimum Quantity Override permission, adjusting an estimate Low Quantity, or charge Quantity below the Minimum Quantity also adjusts the Minimum Quantity to the same value. This is required for the Estimate/Charge to be valid.
As a side-effect of this requirement, setting a Quantity/Low Quantity to zero has the effect of disabling minimum quantities.
If no Minimum Quantity Override is specified, any user may delete a charge or estimate item with a minimum quantity, with a warning, as is the case now.