Mobile diesel mechanic and I want to setup job cards for each of my customers machines so I can log work been done on each of their machine without search all my invoices

I appreciate you for reaching out to us here in the Community, @smmobileplantrep. I can help you with setting up job cards for each of your customers' machines.

In QuickBooks Online (QBO), you can use the project feature to set up the job cards. This is available for QBO Plus and Accountant. You can enable projects through the Settings tab.

1. Go to the Gear icon, then select Account and settings.
2. Select Projects from the Advanced tab.
3. Tap on Edit ✎ to expand the result.
4. Turn on Organise all job-related activity in one place.
5. Hit Save, then Done.

After that, you can create a new project or job from the Project menu.

1. Click on Projects at the left pane.
2. Select Start a Project if this is the first time you are creating. Or select New Project if you've already created one.
3. In the Project Name field, enter the project name.
4. Select the project customer from the Customer dropdown.
5. Add any notes or details about the project in Notes.
6. Hit Save.

Once done, you're now ready to track your transactions to a project. You can use this article as your reference: Set up and create projects in QuickBooks Online.

If you want to add paid and unpaid invoices to your projects, you can follow the steps from this link as your reference: Add existing invoices to QuickBooks Online Projects.

Please feel free to get back to me here for any additional questions about setting up job cards in QuickBooks. I always have your back. Thanks for dropping in, and cheers for more success!