How can I show column totals in a Form?

Hi - I have a form (detail in a master / detail) - see pic of the form.

How can I add a line of totals along the bottom (like you can in a grid)? I appreciate the totals are not a built-in feature of a grid, so I assume that I need a programmatic approach?

I haven’t used a grid here as a grid adds a lot of inflexibility on other things I need to do here, hence trying with a form. That said I am also experimenting with a grid for this, but not being able to update the records (or add / delete etc) has caused me to put that on hold for now (plus the totals don’t line up properly - a separate question in the “grid” forum). If I can show totals in the form then that is much better for me all round.

Any thoughts (using SC8)?

Thanks in advance.

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