I would think about getting a card with 0% on purchases for a year or so- either one like mine, where it's 0% on BTs and purchases, or a separate card from your BT card. With all the other startup costs, it helps to have an interest-free "float" until you get some real revenue coming in.
That's been really valuable to us, as one of our businesses is doing craft shows/Renaissance Faires- long stretches of spending (on materials), then quick bursts of income.
I'm pretty sure you'd still get a hard inquiry on accepting a "pre-approved" offer, but I could be wrong... The advantage of a business card over a normal one is that the normal one will show on your personal reports, and could affect your score (depending on % util, aging, and a whole bunch of other variables). The business card doesn't, as far as I can tell- they just pulled my CR on application and I haven't seen hide nor hair of it on my CR since.
-MsMS