If he is my close friend, he should be 'automatic' and do not take advantage.
I have a colleague who wanted to borrow my for business assignment. He could have easily gotten a cab. I just told him that I do not have such habit of lending people my car!
It should always be 2-way and not single traffic. However, I have colleague who do not bother about 2-way or single way. As long as he is happy, he will do it. I salute him.