How long will you use it for?

The value of something is strongly connected to its function as well as the length of time it will be used. If you solely purchase the lowest priced items, you're going to end up getting lower value many times.

What if you found a great deal on toilet paper? Let's say a year's supply for half the cost of the regular brand. However, the texture was like sand paper. Is the product cheap? Absolutely. Does it have good value? Absolutely not. You're going to be using that product intimately for the next year, every time kicking yourself for having gone with the cheapest brand.

The same applies to many home products (that 5 gallon shampoo you bought might not be worth it, unless you really don't care about what you use in the shower every day for the next six months). If you're going to use it for a long time, make sure you like it and that its use will enhance your quality of life. Once you've found comparable products, then you can select the one that's the lowest price.

Home renovations are another good example. Many people renovate their homes just before they put it on the market. What a huge waste! First of all, they'll find it difficult to recover the full amount they invested in the renovations immediately after the renovations were completey; secondly; they didn't even get to use the renovations. What if they renovated when they moved in? They'd then be able to enjoy this enhanced setting for the entire duration of their stay in the house.

The key - if you're going to use something for a long time, make sure it's of quality.