The payment problem has always be the matter concerned you! Who should pay for the wholesale bridesmaid dresses? Do not be confused with that, your bridesmaid are generally expected to pay for their own wedding-day ensemble (shoes and jewelry included). If you’re a maid and you think the cost is going to be an issue, voice your concerns to the bride. Hopefully she’ll choose casual bridesmaid dresses that are reasonably priced, or consider letting you choose your own. She may give you some color/style requirements (e.g., black and ankle-length), and then each of you would choose something that suits your standards. That way, you decide how much to spend. If your financial situation is truly traumatizing you, just be upfront with the bride about what you can and cannot afford. Everyone has to be flexible.
And if your bridesmaid is the first time to be such a maid of honor, do not be shy to tell her that she has to pay for the modest bridesmaid dresses on her own, she could understand this etiquette.