Hi Bebrite
Welcome to the Community Forum.
Yes you can create a purchase from an invoice. For instructions on how to do that click here: Creating a purchase order from a sale.
You could also set it up as a job. Create the job and link both the invoice and purchase to the job, so then when the invoice gets paid you can run the jobs report and see which purchase is linked to the same job. For instructions on how to do that click here: Creating Jobs.
Let me know if you have any further questions.
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