Hi D==
Much has said so far by the people above. I just want to add some points in the case of the Japanese SMEs.
< $5000 cost>
If you want rather flawless screening, detective service must be employed. And each of the candidates would be investigated from a variety of aspects. In these cases, I know some detective agencies specialized in investigation of job candidates that charge around $3000 per candidate. So it seems that the cost you mentioned is a little high. But it may be rather reasonable if the company that you deal with is outsourcing detective services.
< More Inexpensive Means>
Some Japanese SMEs, which control recruiting process very well, do have accumulated screening techniques by carefully checking the resumes (Rirekisho & Shokumukeirekisho), by carefully watching Google Street Views, and even by visiting their houses. I used to be a professional recruit agent for the SMEs and I sometimes render this kind of service to those SMEs. There must be many so-called recruiting consultants who render this service for you. They would come to your office and do the job for you. I assume the cost would be around $1000 per day. This kind of service only guarantees careful screening which always leaves some possibility of failure.
< Utilization of Jinzai-Shokai Service>
Jinzai-Shokai Service is basically the headhunters in Japan. They can hunt a variety of kinds of people for a variety of industries. As I mentioned above, I used to work for and I used to have some clients in such companies. You could tell them to bring the job candidates for you, telling that you are very conscious of ASF matters. There are many of them which would meet your demand. They charge (in the case of an SME hiring an ordinary employee) you around 30% of the hired person’s annual salary. If the person later within a few months turns out as ASF and you fire the person, you may get your fee back fully or partially. And actually there are some SMEs I know which utilizes Jinzai-Shokai Service only for the purpose of screening off socially undesirable people.
< Trouble-Shooting in Firing “ASF & so-forth” People>
There are some means already mentioned by other people. In the case of the SMEs, sometimes actions of the public organizations (including the police, etc.) are taken slowly and very little. Well, unfortunately they think the SME cases are insignificant. It is true that there are numerous SMEs that ask ex-Yakuza people to settle the issue, which remains barely legal in most of the cases. I witnessed that they were usually quick in rendering the service and very often effective.
D==, I think that the means and costs depend on the quality of the screening and quantity to hire. K==-san mentioned about Yakuza people. They are really suppressed in their activities nowadays. You scarcely face them directly in recruiting. But there are many other kinds of people that are perceived as “socially undesirable people” to hire by the many of the companies. They are normally harder to screen off than Yakuza people.