The prices vary depending on the clinic, and at some clinics it can also depend on how bad your eyes are. Sometimes they run specials, too.
I've heard of prices as low as 1.2m (I think as part of promotions or something), but generally most people that I've spoken to spend anywhere between 2-3m, depending on what they got approved for and other options they may have opted to pay for.
Both Smile and Lasik are more expensive than Lasek, but I think Smile is the more expensive of the two. So if you want Smile and you get approved for it, I'd be prepared to spend a minimum of 2.5mil but probably closer to 3mil.
All in all, don't go with the cheapest place. You want to go with a clinic that has very experienced doctors, and that has a good reputation with the local population.