“However, I am trying to clean up the books from what was done before I got there.”

If this has been used for Tax reporting, you cannot just change this data without review by and with the CPA.

“Every time I create an invoice, the billable time and costs window pops up […]

Resolution for 'billable costs issue: 'How can I clear out billable costs from prev years? No invoices were created by previous users. Pmts entered in deposit screen resulting in neg #’s in billable costs.' available: Yes.

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

For more information about resolving issues related to billable costs in Quickbooks/QBO or to get support for the issue 'How can I clear out billable costs from prev years? No invoices were created by previous users. Pmts entered in deposit screen resulting in neg #’s in billable costs.', click the link below: