This is a must watch video by DesignerJen on YouTube. Jen says the following in her comments:
Remember not to do this all at once, do them through out the next few weeks. The rebates are good till the end of the year. You will get locked out doing it all at once and then trying to redeem your cash right away.
This is under the category “Online Shopping”. Click on the picture and it will take you directly to the video! Of course, YMMV.