how long to foreign visitors stay? Do I have to

No they wont leave well at least my visitor did not leave but, if you go out to eat they just stand in the front of the house when you return home and you have to invite them in and then ask them to spend the night :shock: :shock:

My sim invited his friend to visit then went to work and had an autograph session after work and when he returned home the guest had left and gone back to Egypt.

You greet them at the door and invite them inside. You do not have to ask them to spend they night. I always make sure that I have plenty of leftovers in the fridge for them to eat. Have a guest room with a bed set up for them. My guests usually stay for around four to five days. If you go out on the town with them they don't come back..at least mine haven't so I don't do that anymore. I would imagine that if their needs got too low they would leave, so make sure they have things to keep them entertained and such, if your Sim leaves for work.

I had an old lady from France stay only a few sim hours before leaving and another visitor from China visiting another family for 4 days. I thought I was going to have to ask her to leave. :lol:

I think it depends on whether or not you stay at the house or leave to go downtown to do something. The first visitor, my sim asked her to go to the beach and it was then that she left. The second visitor hung around the house and family didn't go anywhere.