Debug a billing document

hi gurus,

There is a situation in one of our billing documents pricing against a condition type is calculating different one to the expected one, i want to see how the price is calculated for a specific invoice document.

I want to debug this and see how it is calculating the price, and i believe we can see the field values while debugging the specific billing document number. how do i approach this, please advise me gurus as this is important,

i know to put /h in T-code field to start debugging. but my problem is how do i display the behaviour of fields of that specific billing document while debugging.

Waiting for your useful suggestions gurus,

Thanks in advance,

Regards,

Nathan.