Reports 2.5 - invoice-looking design

I'm trying to design a report with a rather tricky design. The result should be as follows:
One fixed part at the top.
A variable number of details following this fixed part. One more fixed part at the bottom - always starting from the same position on the sheet and containing some of the same fields as the first fixed part. It's a typical invoice-looking report I want to create - with a header, an unknown number of details and a paynote at the end of the sheet.

How do I get the last fixed part to start from a certain position no mather how many details there are for this "invoice"?

Rgds
Gunnar

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