How to implement country-specific report in Manager

I have been playing around with report transformations and am very excited about the ways that they’ll help me once I get a few set up. However, I’m having a little difficulty with my first attempt.

I need to generate a report that lists all purchase invoices within a specified period, showing the following columns:

  • Date
  • Supplier
  • Vat number
  • Invoice number
  • Cost excluding VAT
  • VAT amount
  • Amount including VAT
  • Description of goods/services

I have managed to access the data for all the columns, but not the right amounts. For each line item on each purchase invoice I am getting a row with the VAT amount appearing in all three amounts columns, followed by a row with the tax exclusive amount appearing in all three columns. I want the right amounts as per the headers, and I want to see only a single row for each purchase invoice, not for each line item. Is there a way to group by purchase invoice? Or should I be selecting something other than tax_inclusive_purchases from transactions?

I will also need to create a similar report for the sales invoices, but I think that once I figure this one out that will be easy.