Actually - it is the UK tradition for the bride to pay for the bridesmaids dresses, and the USA tradition for them to buy their own.
I paid for my bridesmaids dress. I felt that as I was asking her to wear a particular colour/style, I should be paying for it.
She had a lot of input in the dress, coming shopping with me to choose something she liked.
She used her own necklace (one from when she got married), and bought her own bag and shoes (but sent me pictures to see if I liked them first).