complex if, scenario report

I just need a 'logical' point in the right direction on this one.
What I need to do is create a form or a report where someone can't
enter different criteria and see the results of a calculation based on
the criteria.
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For example, if the vehicle sold is an SUV and gross profit is less
than 3% and salesman is part of a particular team and commission is
1%, give the dollar amount of commission on that sale.
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There would be about 15 different scenarios that include a set of
criteria in each one, but we want to enter different commission
percentage rate and see the results of all the scenarios,
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I envision entering 1 as a parameter (1 % commission) and it runs a
report with all the predefined scenarios similar to whats in the
example above, showing the dollar commission amount of each sale.
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I know I probably didnt explain this well, but if anyone out there
knows what I'm getting at, please help...
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We're basically using historical sales records to see what the
commission would be on those particular sales if we changed the %
based on multiple criteria
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