I have significant experience in this area, and I can tell you that although you will get a variance in opinions, I assure you this field is wide open and extremely profitable. I'll begin by saying that "judgment recovery" is a rather generic term, and although I perform various services related to the term, in NO way do I promote myself as a judgment recovery business.
Why? Because there are several steps in this process, and you have the opportunity to provide individual services that are profitable as well as appealing to a broader base of clients.
A typical collection agency or "judgment recovery" agency attempts to collect or "recover" debts for its customers. This is great and all, but do you want to be tied down as a telemarketer calling people trying to negotiate payments, or settle debts in this economy? I've resigned several large judgment/collection firms over the last 2 years simply because they too are struggling to pay their bills.
So what works then? For starters, its important to understand that before there is a debtor, there must be a judgment, and before the judgment-there must be a legal proceeding. The legal proceeding starts with locating the subject so they can be served. This service is their legal notice to appear for a hearing.
Locating people, or "skip tracing" is extremely profitable, and you can perform this service for law firms, collection agencies, investigators, individuals etc.
Is Skip Tracing/Locating people hard? It can be challenging, however the proper business model allows you to have some excellent sources of public & proprietary data that most agencies and law firms cannot access. Once you learn some basic techniques, as well as an understanding of the best information to pull, you can make a considerable living offering JUST this service.
Average skiptrace/locate fee? $100-$150.00 per subject
My personal highest $$ day performing just this service: $2,150.00
My personal highest $$ in one hour: $600.00
Average time spent per case: $40 minutes