Is there a chance to exchange a green card for a visa?

Question

My friend is going back to his country, he only needs to come back everey once in a while to visit his parents.

Answer 1

Yes, this is done often.

Your friend can go to the nearest US embassy or consulate and surrender his green card using form number I-407 Abandonment by Alien of Status as Lawful Permanent Resident. He should make sure to keep a copy for himself. Then he can apply for a tourist visa, as long as he can convince the consul that he no longer intends to live in the US.