But In reality you just want to collect btc and buy all cards and sell them, but I doubt anyone is going to handover their bitcoins to a new user with no trade history.
You should try to get loan locally from someone and buy all cards then sell them here or try to get loan on btcjam or just take PAYPAL Loan to buy your 4 cards.
Ps: I'm wondering how will you convert btc to fiat and at what rate? Does your supplier accept BTC?
Every trusted seller had a start right? And I wont do such things as low loans etc to get trust, because I don't have time for such games. As I said in thread, and as You described in Your post I collect btc, convert and buy cards. Yes, I could get a loan using my car, etc to cover it all, but I would have to increase price by about ~13%-14% to cover %of the sum I would have to return to the bank which loans me. Plus I prefer to keep BTC running, doing things I can do with BTC with BTC instead of banks, this should be in our interest to do so to keep BTC going.
You doubt anyone will try to trade with me - well I did too, but those who will trade will be rewarded with GPU's for a really low price. I have received few PM's regarding this purchase, and I will have 1 guy buying 3 cards for sure. I started searching for cards like 2 weeks ago, and all this time searching this offer beats other hands down. Keep in mind that prices for electronics here in EU are about 15% higher than USA ones. This is what keeps my offer attractive to the community, and if You invested in BTC You know much about risk, and possible gains which are included with risk ; )
Moving onto Your question - my suplier currently does not accept BTC, I will convert them via bitcurex, either directly to dealers account(he would have to create one and he would ship righ after withdrawal process is initiated), or withdraw to mine and then his. I am secured, even if the BTC drops, unless it drops drastically - then I will return BTC to buyers, but tbh it shouldn't drop that much in a matter of 2 days. Hope this answers Your concerns