Transport working with two forms

JS is not yet completely implemented. 
I am not able to implement JS fully yet.
The transport form is working with the add another form coming on the next URL instead of appearing down the same page. And also, for a particular vehicle_id, the corresponding transportation charges of all the previous added transport objects is being added together and displayed in the generate bill form.
Is it that only the currently (or recently) being added are to be totaled or displayed and not all the previous stored objects? How can I do that?