Hello @itsadesignthing,
This kind of customizations are very easy to do using Premium Templates with no need of code, since this extension includes a customizer that allows you to tailor your PDF documents using product columns and total rows blocks, as well as custom blocks that you can place in different areas of the document (currently 15 different ones). In addition, Premium Templates provides two additional templates: Business and Modern.
For your specific case, you could use a custom block, like this (note that btw_nummer
should be replaced for your actual custom field meta key if is different):
To display your custom field in your invoice:
However, if you want to try using code with the free version, you can use the template action hooks to locate your custom fields on the invoice.
P.S.: I wonder how are you adding these data on the bottom of your invoice, are you already using a code snippet or a custom template?