I don't know the answer to that. I've never seen anything to indicate that there is a problem getting a new visa soon after the first, but that's as far as my advice goes. I suggest you will improve the certainty of getting the second visa if you use an agency.
There is a discussion about experiences with different agencies in this thread:
It's very long, so work backwards. My own experiences were with TZ, and I was extremely happy with the service provided. If you have a European bank account, you should be able to make a simple bank transfer to pay the visa fee, without the need for an intermediary service such as Skrill/Moneybookers. (By the way, someone sold the email addresses of Moneybookers users to spammers.)