Need Advice from the Sifu here:

I have been waiting to buy a SGS since long time ago but was put off the price. Recently I check the price on internet. Generally AP set cost around RM1.6-1.7K (16G) and RM1.5-1.6K (8G).
I can see the price is dropping and I found one seller in PJ selling 16G for RM1.45K. Could this be true? This company seems like a reputable seller on this particular website and they have a shop.
Since I am not living in Klang valley, I will probably ask a friend to buy on my behalf. What are the things that my friend should look out for when he check a SGS?

Sorry for my long winded query and I thank those who answer my question in advance!

Thank bro, may i ask what is the difference would the set up make to my phone? what is the acceptable rom anc ?