The savings, if any, is going to depend on how many grafts you need. If you are only need 1500 grafts then you're probably not going to be saving much after you factor in air fare, hotels, and food. If you require over 3000 grafts then you are going to start seeing big savings. Without knowing your situation there's no good answer on the savings.
With that said, you do need to be careful about where you go. Don't just look for cost savings. Getting a bad hair transplant will cost you more after the required fixes, not just in money, but also time and emotional issues. It's not easy living every day for a few years with a botched hair transplant until you can get it corrected.