We have hosted a few exchange students during the summer months. We had a 20 year old guy from Africa, a 21 year old girl from Russia, a 19 year old girl from Italy, and a 20 year old guy from Mexico.
I would never do it for longer than the summer months. By that time, everyone just wants to be back to normal. The only problem I had was the man from Africa. He expected his laundry to be done, food on the table, and he had a mentality that women should always be in the home. I worked full time so he really held that against me.
It can get very expensive to host someone. I always wanted to make sure that they saw it all while they were here in America. It was really my own fault for spending so much money on them. I have nobody else to blame.
The hardest working person I had in my home was Armando from Mexico. He cleaned dishes, did housework, and was the nicest, most caring exchange person we have ever had. The others more or less just expected everything else to be done for them.