Assuming that the person is eligible for an immigrant visa, the government fees will depend on whether the person is adjusting their status in the United States or at a consulate in another country. To adjust status through a family member in the United States can cost anywhere from $1490 to $2490 in application fees and more if a waiver is required. For someone to process from abroad the fees are normally from $738 to $1323 if a waiver is required. These fees are not necessarily all payable at once and may be in stages. However, in order to know which process to follow and exactly what the fees involved will be, I recommend that you meet with an attorney in your area who can evaluate the situation and give you an accurate account of the fees involved in the case. Good luck!