How fancy are you looking for?
What do you mean by “arrangement”? Table center pieces, favors, general decorations, veil?
If you don’t need to have them all match , I’d check out places like Ross, Marshalls or TJMaxx. If you have more time, more creativity and enjoy that type of look, also check out your local thrift stores and estate sales.
Have you looked at Recycle Your Wedding? You might be able to find a lot of gently used items to spruce up your wedding for a steal.