Vases are vases, whether cheap or expensive. Yes, the quality matters, but you should know how to decorate them in a manner that will add to their aesthetic appeal. They add beauty when used as center table pieces or as basic decorative purposes.
It could be tall and cylindrical, square or rectangular, globular, tear drop shape, test tube shape, or in various other shapes. There are a lot of cheap glass vases for wedding centerpieces that are available in irregular shapes and sizes.
While these are universal favorites, think a little out of the box, and fill up a vase with wood shavings. These have a beautiful, earthy decorative quality about them. For an additional element, you could place a small tray within the vase, with a tea-lite or a small candle in it.
For further interest, layer your vase with sand and shells, and see how beautiful they look. Place this vase next to a water feature (such as a fountain, if you have one) in your home. These can also be used as cheap wedding centerpieces. You can also paint the shells in different colors, and see how beautiful they look.
This idea is less than outrageous, but definitely out of the mundane. Decorate your vases with dried orange and lemon peels, and add a few fresh or artificial green leaves in it for a contrast. This is a wonderful, refreshing sight for the eyes. Place it on your dining table.
If you happen to get hold of cheap glass vases that are as thin as test tubes and taller, then adorn them with a single flower each in different colors.
Knowing how to decorate them can make your vases look as pricey as the expensive versions you may have seen at different stores or in your favorite catalogs.