Supposed guidelines of Dos and Donts with Japanese Host Families

Before I talk about my host family more, let me mention how life with a host family was supposed to work:

All of the international students were previously talked to about rules and issues that may be experienced with a host family.
One rule would be to never walk around with shoes inside a house, and to wear slippers around the house whenever possible.  It was also suggested that students should buy these slippers on their own if possible so as to not inconvenience the family.

With showers there were also rules and guidelines.  Students should observe the order in which the family takes a shower, as there may be an order defined by social status within the family.  Also, the student should be prepared to buy their own towels and bath supplies as a host family might not want to share with anyone but their family.  Also shower timing may be important, as apparently most japanese shower only at night, so a person wouldnt want to shower in the morning and risk waking family members up.

There were also issues of ownership.  Students should not expect to have a key to the host families house, as students are just visitors.  And the fridge should be considered off limits.  No storing or taking from the fridge as it would be rude to make yourself at home in someone elses house.

There was also mention of laundry.  Students should not expect the family to do laundry for them, and they might want to buy their own supplies to do laundry.

Also, food.  It is supposed to be rude to not finish a meal in Japan.  And with all the crazy food they could eat, I imagined that it would be a huge issue.  I also found that they eat really large meals compared to how much I can eat at one time, so that's another issue for me.  I haven't really seen many/any fat japanese, so what they are eating may be a lot, but either it isn't fattening or they just have good habits to keep weight off.

Last guideline that comes to mind is the issue of speech.  Verbs have plain and formal forms and commands like please do this/that have varying degrees of politeness.  So, being a study abroad student it makes sense that you should be on your best behavior and use polite language at all times.  This also extends to naming.  There are suffixes to names in Japan which denote social status relative to the speaker.  You'd want to make sure that you refer to your host parents in a respectable way.