[odonata]

Go with Sakura or Oakhouse and you should be looking at 100,000 yen or less per month, so thats about 500 quid per month.
As for food, cook your own most of the time, it works out cheaper then UK if you know where to shop plus the quality is 10 times better.

Today I bought about 850g of chicken (boneless) for 658 yen plus a good lump of beef for 1014 yen. I went to Hanamasa for that. That will provide me with a good few days top eating.
Eating out every day is a mugs game and is the trap that many people fall into.

If you want a cheap and productive trip here then you need to behave like a local and not a tourist and you don't need to speak the language to do it.
Donkey (Don quixote) is a good place to buy a wide range of essentials but visit a 100 yen store first to save a few quid. I can get a bottle of Chivas Regal at donkey for about 12 quid and the same in the UK is about 25. Also Smokes are about 1.50 per pack as opposed to 5.00 in the UK.

I am a sukker for beef and love my peas with it. I just bought 1Kg of frozen peas for 1.75 GBP, in the UK that would have cost me 3.20

If you want Japan so bad then consider a stay of at least a month. This is my budget for this trip in GBP

Return flight (Finair) 540.00
Single Private room. 400.00
Room includes TV/Fridge/Bed/Futon with shared toilet/shower/kitchen/washer dryer.
Weekly food shop. 40.00
Dining out Aprox. 20.00-60.00
Suica travel card per week. 10.00-30.00 depending on where I am going.
Most other stuff will depend on what I want to buy and how much I want to spend.

If you will buy clothes then do not pack too much to come here. I only came with 2 x jeans 2 x shirts some socks and Upants and 2 x teeshirts. Bear in mind that I was wearing one set to travel. I expect to spend about 3-400.00 on clothes to take home.

You could prob do a month trip and have a good time on about 2000.00 GBP
Sounds alot? To live for a month in the UK paying room and board and all the other things would cost you closer to 3000.00

Marc.