sevenel_mx
those prices look fairly good to me,If I remember correctly when I changed one of mine over to 17's,the whole set on tyres was like I say going from memory,set me back $1180,you are allowed to change the rolling radius of the factory wheels by only 3%,when I first got mine to stay legal in WA I ran 215/50/17's,I now run 215/45/17's as these seem to be the most common size used on the mid sized cars these days thus a little cheaper and easier to get than the 50's.
But be aware if you go to either 17's or18's 1/ you tend to harden up the ride and 2/ you are at greater risk of damaging tyres if you happen to hit any pot holes,I speak from experience by ruining two tyres in the past eight months on our beautifully maintained country roads,I have been in similar situations with our second I30,it has stock 16' factory mags and we have never damaged tyres on that one.
Bob Janes a good place to go too,they have all the software programs to give you all the correct information,plus they have a very goodselection of wheels and tyres in all different price ranges to suit your budget(and no I have no association with Bob Janes)
Oh and welcome to the forum,notsure whether I have welcomed you to the fun house before,you'll love your new car,I still get a kick out of driving our two and their both two years old now.