I lived alone in Japan for two years from 2002 – 2004, and with my wife from 2004 – 2007, so although my knowledge is not right up-to-date, I don’t see things having changed significantly, due to a stagnant economy and declining population.
Rent on a small apartment can vary considerably depending on the city (even outside Tokyo) and the size and quality of the apartment. A 1DK (1 bed/living room with a reasonably sized dining/kitchen room and a separate bathroom) should set you back between ¥50,000 – ¥70,000. You don’t really need anything bigger, but you should expect to pay between ¥10,000 – ¥20,000 per month more for a 1LDK (as above, but with a separate living room). You should be aware, though, that setup costs for apartments in Japan defy all logic. You may be expected to pay a deposit equivalent to up to 6 months rent. You will also have to pay the estate agent, and in many cases may have to make a “gift” to the landlord of up to ¥200,000 (although it’s often cheaper).
You might find that some (many?) landlords will not let to foreigners. Your Japanese university will be able to advise you on which agencies will help you find a place.
A week’s worth of groceries will vary depending on what you want to eat, obviously. I paid maybe ¥10,000/month, but I was going out a lot and was happy to eat light meals for most of the week – cheese on toast, cold meats, salads, etc…
Japan is great for good food on the cheap. Head to a yatai for awesome ramen at around ¥600 a bowl. You can go to a yakiniku restaurant and get an all you can eat (食べ放題 :: tabehoudai) deal for ¥2,000. This can be an all you can eat and drink ( 飲み食べ放題 :: nomitabehoudai) deal for ¥3,000 – ¥3,500). Yakitori is also cheap and very good. A good meal at a sushi restaurant can be expensive, but the kaitenzushi (conveyor belt sushi) restaurants charge per plate, and the colour coding makes it easy to keep track of cost. You should also try out some of the millions of izakaya in Japan. They’re like a pub that also serves cheap food from a range of countries. The mayonnaise pizza is best avoided though. Places like Yoshinoya and Hokka Hokka Tei also do really good, cheap fast food – often a bowl of rice with some meat in a sauce on top (it’s better than I make it sound).
You’ve probably guessed that I could write for hours about Japanese food. I’m going to stop here, but feel free to ask me a specific question about it.
Public transport in Japan is a mixed bag – the buses can be very slow due to the volume of traffic, but the trains are AMAZING. If a train is a minute late, you’ll get a guy on the tannoy apologising. If your train to work is significantly late, you’ll be given a letter of apology from the rail company which you can show to your boss. The trains are not cheap (they’re cheaper than in the UK, actually, but that’s a different story) but they are comfortable, clean (oh so clean), and punctual.
A bottle of beer in a bar will probably cost you between ¥500 – ¥750 depending on the beer. You might have to search around for a bar that serves your favourite, but Japanese beers are excellent – Kirin Ichiban is a good mass-market beer, and Sapporo beers are also very good. In Fukuoka (where I lived), there was a hyaku-en bar (¥100 bar) which had a cover charge of ¥1,000. After that, you were charged ¥100 for every ten minutes. Many bars and clubs also operate a nomihoudai tarriff.
Beers from the shop are maybe ¥200 a can/bottle.
In terms of general advice for living in the country, you’ll find that the Japanese will – generally – be extremely polite and helpful towards you. I got on the wrong train in my first week in Japan and ended up in the wrong city. An elderly woman put me on the right train, and then got on it too to make sure that I got off at the right station, even though it was out of her way.
Expect:
… to be stared at.
... to feel “foreign” (well, duh, but Japan is a particularly good example for a Westerner)
... many people to get nervous around you.
... to be popular with the ladies (or men, if that’s what floats your boat).
... to experience culture stress.
... to be asked questions that you consider personal by complete strangers.
... children to be scared of you.
... people to not sit next to you on the train if they can avoid it.
... to not have a fucking clue what people are saying (unless you study Japanese)
... to be laughed at if you make a simple mistake in Japanese.
... people to ask you for English lessons (it might be a good idea to take an ELT course before you go – you can work for a 20 hours a week on a student visa, I think).
As general advice, I’d say the single best thing to do before you go is to study Japanese. It makes your life so much easier.
Oh, And DO NOT GET ARRESTED. Even if you’re later released, you’ll almost certainly lose your university place, any part-time job you have, any Japanese friends you make, and possibly even your apartment. Conviction rates from arrests in Japan are astronomical – 95%, I think – and you won’t be given access to a lawyer or translator while in police custody. Do not let on if you speak any Japanese.
If you have any questions, feel free to ask.