QBO only has one unit, each

You create the items for the rope and pipe, you set the qty so that a qty of one = the unit you sell in.

Rope if you buy a roll of 250m of rope and sell by the meter, then you stock each roll as […]

Resolution for 'buy and sell issue: 'buy and sell in different units' available: Yes.

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

For more information about resolving issues related to buy and sell in Quickbooks/QBO or to get support for the issue 'buy and sell in different units', click the link below: