/fa/ - Fashion

Just got a commissioned sales job in a retail setting. I am an independent contractor, not staff, so I don't wear a uniform. Was going to wear an oxford and some dark jeans, but I'm wondering if a blazer is too much. I'm supposed to be representing a joint venture between a major bank and a drug store.

Trying to sell as many credit card applications as possible here, so I want to look professional.

And yes I'm already a longtime /fa/ lurker, I just need some second opinions regarding the "formality scale"
What clothing will help me make lots of sales /fa/?