scorz wroteHello there my aunt is married to a Japanese dude so I'll try to answer some of your question.
1- Not so hard. Visa is basically easy to get I guess.
2- I am not really sure.
3- Yeah my aunt lives there:
- Life is not so easy because jap are like machines.
- Earthquakes are a pain in the ass.
- NEVER mess with yakuza or any other gang member.
- NEVER EVER try to buy weed, you will be banned forever if you didn't go to jail. Law about weed/drugs is so thought.
- Sushi is NOT like what you eat here.
- Japan is Expensive.(ONE lettuce leaf cost 4USD)
4- Don't know.
5- No matter where you live, if you're going as a student it's going to be expensive. Most of universities are located in major cities, (Tokyo, Kyoto, Osaka, Nagoya...).. Even if you're going to live outside the whole city, you'll never make it to class at time using metro at rush hour.(PS: Metro is also expensive)
6- Forget about it. You still in first year anyway, so pursuing your doctorate is not before 5 or 6 years right?
Japan is not your best country for education(Unless of course you live there) There is plenty of reputable universities in Europe/America where it's cheaper and life is easier.
About the expensive part, may I ask in what city your aunt lives in? (Different cities, different prices)
By "sushi is NOT like what you eat here", do you mean it is better or worse?
I know there is a lot of time left, but its better to always plan ahead. Even if it is just a little :)