From my personal point of view (from my own experience) I get so many calls wanting to see whatever I got to offer, I cancelled all my plans. Then they never show up plus reject my call. They sort of disappear or something as you never hear from them again. So now I understand why some people put 'no time wasters'.
I also get too many calls asking for what is your final price. Thus, final price is stated in the add. It's like they can't see the price already. I guess to some seller it's their final price for that week or so. Then they decided to consider lowering their price I suppose.
So yeah, my two cents