You will presumably have a merchant account with a bank? Then you are fine really I mean the QSA companies do not ask for this.
I mean I am a freelance web developer, I don't have a merchant account yet work do and when I was going about starting off the scanning of our terminals they never actually asked about any merchant account.
The only thing I should warn you though is there's actually 2 forms of checks they do, one where they try scan your network (I mean most of mine's from a Internet prospective, but it's the same in a sense for the terminals as well, since you are seen as a branch on their network), I think from memory that was roughly between, well I didn't see any quotes above £200 maybe £250 put it like that.
The penetration testing which does not have to be by a QSA just someone skilled enough to do that work of actually trying to break into the network, again most of this is from my own perspective that's allot more costly but puts your mind at ease in a sense, there's different bands to how many times you are checked for any security flaws which again I can not remember.
They won't give you any quotes on here but there's a general guide on here the sort of actual councils website:
https://www.pcisecuritystandards.org/
Though I have to say Paypoints now changed from sysnet and have an online assessement over your requirements, they asked for a merchant account, some will I think some won't.
But the penetration testings is always the most costly, but compare about £2,000 with a fraud forensics network team being paid roughly according to my contact at Sysnet (which I have not spoken to for a while) would cost the credit card companies at least £20,000 per day on average, it's about £2,000 an hour they charge if a customer reports a fraudulent transaction it's not cheap.
Also once you are PCI Compliant some QSA's will do the penetration testing as part of the whole deal and give you insurance should a breach of the network take place, of which you will pay an upfront fee for but they end up paying the whole cost of a fraud team.
I hope this is actually making some sense it's a hazy area to go into since network security always is but it just saves you from the possible threat, though I do have to say not allot of companies in the world at large are actually PCI Complaint to be brutally honest with you, infact much less than half still.
This was the case I was warned about:
http://forums.theregister.co.uk/forum/1/2008/03/18/hannaford_data_breach/
Here's some general help on the matter:
http://www.info4security.com/story.asp?storycode=4123335
There's about 3 charges you are given some of them multiple, if a breach occurs any fraud that's actually commited as a result of the breach is then refunded to by the merchant (if it was the merchants fault Visa are a pain for this, they try to blame the merchant as much as possible), a charge is then applied to each transaction that's refunded and then the fraud network forensics team put their charge on it, I can't remember how much TK Maxx where charged but it was not cheap, but then their a big merchant you're most likely not.
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