
First kid went to nat'l uni in osaka, cost was about ¥2.7-2.8 million/yr (we don't live there). Add a cheaper year (there) in juku beforehand, since she didn't make it in the first time. A little over ¥2M for that. Probably ¥13M total.
Second went to public, but in tokyo (don't live there, either). Farther away, and more expensive--¥3.3M/yr. Plus an extra exchange year abroad, which was a little cheaper than tokyo. Probably ¥15-16M total.
That's everything we funded--school expenses, housing, trips home, basic spending money. The both worked, for extra spending money and then any trips they wanted to take. In each case it could have been done for less, but it could have been done for more. We (and they) weren't cheap, but we weren't extravagant.
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It was worth it. They graduated, and haven't asked for or needed money since. Older one (now 31) makes good money (chem major), her husband more, and her job is such that she's had two year-long maternity leaves (has returned to work twice now). Younger one went to the states, worked in a uni lab for 2.5 years (full time lab asst), and is now in a fully funded phd (one year done).