Hey Maushan,
Living in a gaijin house and going to a language school with a high concentration of English speakers is not my recommended lifestyle for learning Japanese effectively.
Actually I recommend getting as far away from either of those options as you can. Schools in the countryside are more likely to have dormitories than schools in Tokyo. Even if they don't have dormitories, renting an apartment for 30,000yen/month your move in costs will be similar to one month in a gaijin house and you'll save a bundle in the long run.
On nisshinkyo.org you can browse a database of language schools by region, etc..
On apamanshop.com you can search for apartments and get a good idea of the prices in the area.
I've never heard that you can't get a pre-college visa more than once, but I do know that it has a maximum of 2-years. I would think that if you were in Japan for 1-year before, you could come back on a pre-college visa again as long as your intended length of study at the language school is officialy 1-year. That's something you'll want to ask the consulate though. Otherwise you'll probably only have the select few language schools that are able to provide college student visas to choose from.
Hope this was some help, Good luck,
a7mouse