2001 Kia Sportage Transfer Case is going out, I can buy a used one for $180, how hard are these to replace? Any advice?

not that easy, it's pretty heavy duty work moving all the parts out of the way and installing a new one. But, if you have arms and good jack stands and a solid driveway, why not try one weekend?

Do I need to remove the tires, front drive shafts or will the drive shafts be removed from the transfer case?