You have integration between Jobs and Sales Invoice, but this integration is only when you want to create Invoice with Job by 'Job Create Sales Invoice' batch. You use this batch job to create an invoice for one or more jobs. You can also choose to create invoice based on Job or Job task.
There is not exist integration between Jobs and Sales Quote.
You can use Jobs in Purchase Order, but if you use it for item, you will not get inventory stock. System in the same moment post recipient and consumption per job. But when you create sales invoice, system will calculate these items in invoice.
If you need something else, please give us a more details.