Lets think of this in terms of a pizza and a coupon.

We didn't have cable tv (still don't), I clipped coupons (still do), pretty much didn't spend money on anything unless we had to. 

It's the same as receiving a burger king coupon in the mail.

Also if you bring in coupons from Lowes like 10% off your full purchase price, we use these.

A few bottles of water, a coupon to a local pizza place and 4-pack of toilet paper (just $1 from the dollar store) can really put on smile on your new tenant's face that first night in their new home.

McDonalds breaking the tire iron out on someone trying to use an expired coupon. 

It's great when you want to input different values to see what the return would be at XYZ coupon payment, or to backtrack into a price based on a 12% return, etc.

That was a coupon on Angie's list :-).

I've been using the $10 off coupon for BP Pro members for 2+ years now and have had only a few minor complaints.  

If you have a payment coupon that indicates additional principal fill in the line.