When going through stacks of paper, people often feel the need to keep them so they can re- read them. Be honest with yourself, look back at the times you actually did do this. Look at this objectively and you will realize that in actuality.... you never do. So ask yourself why you keep this...........

What I tell myself when dealing with paper I am doubting about, is that I am setting it free and allowing it be re- used. When I keep the papers, they will end up loosing all purpose and will just be in my way, since when I thruthfully look at my use of them, I can say I never re- read any of this.

So you are worried something valuable may lay in that pile of paper of envelopes and ads.
Tell yourself the following:

PAPER.
This is a trick I use for myself and which works wonders. When I am in doubt whether or not to keep a paper, like whether that receit will truly be worth saving, or that magazine with a really interesting article I will probably never read anyway or that ad that has such a cool picture......... I close my eyes and rip the paper in 2.
Does 2 things, ruins your ability to read this so why keep it and it doesn't interfer with it being able to be recycled.
I actually tend to do this with most papers and once a bag is full, I look at that and realize there would really be no use into keeping this.
Just be hard; close your eyes and rip in 2.
No looking back, just doing............ Is kind of all or ntohing thinking, but helps me when I am doubting. May sound strange to actually feel relief from not being able to get the paper back, but if you try this, you will see it not only brings relief but it also gets easier with each time.

ADS.
If the ad really is the opportunity of a life- time, you surely would have sent it in already, if you didn't it probably is already too late so why keep that. Not only that, chances are very likely that the ad was just trying to sell you something, don't fool yourself, companies seldomly "give" you something for free.
Ads will be resend and you probably won't look at them then either. The purpose of ads is to be sent often and in bulk.
So you can safely throw those out without missing out on any chances.

BILLS.
If ever by accident you throw out a bill that still needs to be paid, know that credit- owners most likely will send you another 1 to remind you of that. If you forget about them, you better be sure they don't. But to avoid all hassle, buy yourself a map or box in which you will always put your bills.
Make it a rule to IMMEDIATELY place bills there.
Don't wait with such things, if they arrive, deal with them right away.