HTML radio inputs are not meant to be multi-selection.

HTML input type="radio" (w3schools.com)

If you want multiple selections, you should use checkboxes; you could use CSS to make them look like radio buttons, but that is counterintuitive based on standard web UI behavior.

HTML input type="checkbox" (w3schools.com)

Radio buttons are an either/or input type and I would not be surprised if there was unexpected behavior caused by trying to make them behave like checkboxes.

Additionally, if you're using calculations to sum up the total, hidden values are not automatically excluded from calculations while you are filling out the form.

You would need more complex calculations to ensure the values from those input fields are only factored into the total when the corresponding box is checked.

For example,

=SUM(IF(Checkbox.Option1,Field1_Cost,0),IF(Checkbox.Option2,Field2_Cost,0))

When you have checkboxs on a form, you can reference them for TRUE/FALSE in calculations, so in the example above it only adds Field1_Cost to the total if Option1 is checked, and so on.

If this is part of a table/collection, the calculations would be a little more complex.