Collection costs would be added to what the person owes, I would think. In the OP's case at least, I'd ask the judge to include that in the judgement, given that the customer has already demonstrated a reluctance to pay.
The court will not preemptively award estimated collection fees since you have not yet been burdened by them and they are unknown. It's not like a regular civil case where attorney's fees are known by time you are receiving judgement.