Have you ever seen a deal for something, let's say toilet paper, turned to a family member and said "But wait...how much do we normally pay for that?"
I do that all...the...time. It's obnoxious to my husband who never remembers prices and annoying to me to not know if a deal is really a deal or not.
So, come up with a Master List. It's ok to start off small with just a few items you use a lot of- say toilet paper, soft drinks and paper towels. You can build your list as you go.
You can keep this all handwritten in a notebook or just scribble the numbers and enter them in an excel file later- really it's whatever is most helpful for you! I keep my Master List written by hand in my coupon folder, where I can always grab it quickly, though I really need to put it in to an excel file just in case I lose it!
Write the average price of several stores- say Walmart, Target and your local grocery store. You don't need the average price at EVERY store around, just a few of the "biggies" your normally shop. Not only will you know where to go to buy the item regularly, but when they do the "roll backs" and "price cuts" you'll know if it's a REAL deal.
I suggest putting the regular price in one column, then the price per unit in a second one. Price per ounce, per 100 sheets, per roll, whatever. Just make sure it's equal across the board. An example of things you need to track might look like this:
Date/Brand Name/ Store/Size/ Price/ Price per unit
1/17/11- Coke- Walmart- 2 liter/ $1.49/ (whatever unit it may be in- whether you choose to just put 2 liter here is fine because in this example, it's a standard size. This is more important for things like Toilet Paper, because roll size varies greatly among stores like Walmart and CVS).
1/17/11- Coke- Target- 2 liter/ $1.50/ $1.50
See? Easy Peasy. The important thing is to keep your book updated at "regular" prices and not only concentrate on sale prices or rollbacks. For instance, if you have your handy dandy Master List with you when you notice Cokes are "on sale" at CVS for $1.25, you can instantly recognize that is $0.25 cheaper than Walmart's average price. Not a stockpile price, but not bad if you need to pick up a single coke. However, let's say you know Walmart normally charges $1.50 for a 2 liter Coke and they are running a rollback price of $0.88. That is significantly less than both Target and Walmart's normal prices, so it might not hurt to grab a few at that price.
Too easy? Want to get more in depth? We can do that!
If you're really committed, enter the price every time you go shopping. This will help you identify sales cycles. Say every 2 months, you notice Walmart puts Coke on sale for two weeks. Well, then you know to buy enough Coke to last you 2 months, then you can stock up again during the two week price break.
If you don't want to get in to the sales cycles, your more simple Master List of regular (non-sales) prices is helpful when you're flipping through sales circulars each week to say "Hmmm, Coke at CVS for $2? NOT A DEAL! Coke for $1.48 at Walmart? That's only a 2 cent break! No reason to rush right out!". I do recommend at least updating your prices once a month or so, to account for regular inflation.
It takes literally seconds to do, especially if your list is short! I think you'll be pleasantly surprised how much time (and gas! and HEADACHE!) your master list saves you. No more rushing out to get THE DEAL of the a lifetime, only to head to the next store and realize it was 10 cents cheaper regular price.
It can be as simple or as in depth as you want it to be. After all, this is a tool to help you!