Guys, iam so concerned w this 
My 1st preference is B of Com ( atar of 93 required ) . I have received an email from the school 93 is guaranteed entry, so is there any chances i might loose it ( i got 93.25 x_x )
It would depend on the year's cohort, the demand for the course and a little luck. It often changes a little, give or take. The VTAC Course search stuff is a general guideline. You are above the clearly-in ATAR required, however, it may or may not change, so (my thoughts, not facts) you have a high chance of getting in (that's a really good ATAR), but it's not quite guaranteed. If you're a doubter, relax. That's an amazing achievement and probably will get in for Commerce. Don't fret it.