I know that I came with all my uniforms in this past prep school year. Although I wasn't issued new uniforms other than the officer service jacket, they still charged me the same exact amount as they charged anyone who came in direct who were issued full sets of ABU's and Blues. Also, on the packing list, they told us to bring things like a backpack, the v-necks, socks, etc, but all these things were reissued and we were charged for them. PT gear was reissued, along with 90% of our packing list and it was all charged after having purchased it prior to arriving.
To be fair, I think the reasoning behind the people with uniforms being charged the same as those without was that this was considered the "initial uniform issue" because they are "enlisting" in the Air Force. I had asked AAFES for an itemized receipt with everything charged, and they were very uncooperative. They refused to let me see what I was being charged for. The book store was the only group that let me see what they were charging me for. Other than that, AAFES just flat out denied my requests.
Also, if you are prior enlisted, bring money or a debit card with money in your account. For that first week, we ended up having to buy every meal, and I don't think we were ever given BAS for it either. Breakfasts were at Mitchell Hall, I think like $3 a day, lunches were boxed lunches, again, I think like $3, and dinner was, you have your phones, order take out.
Finally, priors who are in need of more ABU's, check out the Airman's Attic. I think they give out free uniforms to anyone who is a SrA or below.