Beware of the rebate coupons!
sometimes you see the ad saying buy something for 39 and get 20$ rebate

You got to be careful. They count on you being lazy or forgetful

Act on it quickly

Print your return address clearly. A printed return address would be helpful
Make a copy of the receipt and UPC
Mail it within the due date
Note down the 800 number to call

Wait for 2 weeks and call the number to make sure things are ok
Don't wait for 8 weeks
Call them definitely at 8 weeks. sometimes they act only when you call
They sort of count on the fact that you may forget
You run into problems with smaller manufacturers

Ram