Collecting from deadbeat customers

I hate to admit it, but I feel your pain. I've got about $6K in bad debt I'm carrying on the books. The original # was closer to 10K
I've turned some of it over to a collection agency, and they have have been hounding some of these people to death. They have managed to collect or caused people to bring me some money.
I have mechanics liens out on some property, so sooner or later, that will get paid. The ones I loved were the bad check writers, oddly enough, I collected the last one of those this past February. Last X-mas eve this guys mother called me and asked if I would be willing to drop the warrant I had on him. It would seem the police came to her house and arrested her son on X-mas eve.
I told her I sure would, I need the $65 for the bad check, $70 for the bank fees and $250 for my bad check fee. Mommy wouldn't come off the $385 and junior spent X-mas in jail. It went to court, he was ordered to pay by Jan 24, he didn't. he was re-arrested and posted bail (which was $385) and I got paid that way. I got paid and he spent 4 days and arrested twice over a key.
If the amount is large enough, I would contact a collection agency and/or file a lawsuit. Most times you can get any or all legal costs involved in the suit. it's a huge pain, but worth it. Mind if I ask what the debt is over?

I did some consulting work for the company I mentioned... IT/computer stuff.

The amount owed is nearly $40k.