Flooring for Rental

[James Masotti]

I know this question has been asked a number of times...but I'm really struggling on this for some reason...and am looking for those of you more experienced to help me make some sense of this.

The new rental I'm scheduled to close next week is going to need new floors. Originally I didn't think it was going to...but I just wouldn't be comfortable renting it in the condition that it's in. I'm buying this deal pretty well...so I have the room for adding the flooring.

What I'm struggling with is what type of laminate to put in...I'm hearing lots of different opinions that 8mm is fine...and others saying going with 10-12mm? Does it matter if it's AC3 or AC4? If it comes with a pad, should I still put down a secondary pad? 

I'm also struggling with the price discrepancies of laminate flooring. Other than aesthetic differences...what's the difference between $1.29 sq.ft. and $2.19 sq.ft if both are 10mm AC3 click-lock construction. Is there any reason to spend an extra $1000 on flooring when on paper the physical specifications for the two products are the same?