One shopping tip I find very useful is to make a list of things you need and/or want with dimensions, reasons, and other info. It's wonderful for those situations where you're at a flea market or garage sale and something catches your eye, but you're sure if that something would be of benefit to you.
The most important thing is to carry the list with you.
Had I been carrying my list on Tuesday I would have realised that the wonderful purse actually fits the description of an item on my 'needed and/or wanted' list. I've been looking for a large purse to use as a day bag while traveling. It would have to be large enough to carry a wallet, guide book, notebook, lunch, snacks, water bottle, camera, and a change of clothes and toiletries when just popping into a motel for one night while on the road, but not be so big that I would be tempted to stuff the kitchen sink into it. I also wouldn't want it to look like a travel bag.
So, two days later, after obsessing over the darn thing, I went back to the store, looked the wonderful purse over, checked off all the requirements, and bought the darn thing!
"Life's but a walking shadow, a poor player that struts and frets his hour upon the stage and then is heard no more. It is a tale told by an idiot, full of sound and fury, signifying nothing."