In my country, there are no lawyers in small claims court, so there'd be no attorney fees. The only cost other than time is usually the amount of money charged by the bailiff you hire to deliver the Summons or whatever the document is called.

So if a client refused to pay you $3000, you take them to small claims court for $3500 or whatever (you have to convince the court that these extra charges for the bailiff fees, your transport to and from court, etc, are just).