Thanks to William for sending me this link. It contained some of the most comprehensive information I could find on visa self-sponsorship.
Here are some excerpts:
The Initial Requirements Requested
1. Certificate of "Retirement" [a taishoku-shomeisho 退職証明書] from the last company who sponsored your visa
2. Certificate of Employment from your current companies/agencies (jinbun chishiki kokusai gyomu)
3. Payslips [kyuryo-meisaisho 給料明細書] for the past year
4. Tax forms for the past year
5. Invoices [seikyusho 請求書] for any private students you will be paying tax on (i.e. any agency who will be filling in a Certificate of Employment for you)
6. The Department of Immigration three-page "Application for Extension of Period of Stay" form
7. A cover letter explaining that you are looking for a self-sponsored visa.
They told me there would be a 3 - 4 week wait.
Most importantly, I did get an email that same day from another friend who had applied for a self sponsored visa in December. He was granted a full visa and he only handed in copies of his contracts (and nothing else)!
Amazing - it sounded like I actually had a good chance, like it might actually be quite a reasonably easy process. Just as long as you can prove that you are earning at least 250,000 yen, although I also heard from one source that someone who earned only 220,000 yen received a self-sponsored visa last year. Could be just a rumor though.
15 days after I put my self-sponsored visa application in, I received my notification postcard back.
I went to the "approval stamp" counter and waited in line for 20 minutes. The woman took out my folder, glanced inside, asked for the 4000 yen stamp (purchased from the convenience store downstairs), gave me ticket number 32 and asked me to sit down and wait for my number to be called.
15 minutes later, 32 came up. The woman handed me my passport, open at the golden, gleaming new approcal stamp, told me to report my changed status at my ward office and then went back to her paperwork.
That was it. Done. Too easy.
Too easy indeed. Although it does sound like the paperwork can be a hassle, there are some important things to note:
1. Apparently the laws or enforcement of the laws surrounding self-sponsorship are somewhat arbitrary; different paperwork is required depending on the office you go to, the person you talk to, the day you arrive. Just bring everything to be safe.
2. One- and three-year visas are available by the self-sponsorship method. Although you are "self-sponsored", your visa still falls into the category of your job type (i.e. you maintain a "Specialist in Humanities/International Services", or "Entertainment", or "Instructor" visa). The only difference is - no employer backing your paperwork.
3. Even the monthly income requirements seem to be up in the air - between ¥200,000-250,000 minimum, depending on many factors.
4. I'm not entirely certain about obtaining a self-sponsored visa prior to a working visa; it may not be a rule that you have to have worked in Japan before sponsoring yourself, but it may give the bureaucracy the leeway to make you jump through a few hoops.
I'll start gathering my paperwork together and let you know how the process goes. Of course, if I find a suitable sponsor before then... moot point. Any advice? Wish me luck.
In Hiroshima Prefecture, there is a hotline available for those with visa-related issues. Call the Hiroshima International Center at 0120-783-806 or 082-541-3888 on Tuesday, Wednesday, Friday, or Saturday from 9:00 AM to 1:00 PM.
Jobs in Japan self-sponsor information
The best story I've read about self-sponsorship
Ministry of Foreign Affairs in Japan - Visa Information
Gaijinpot Forum - visas