For any other credit, consult with your tax professional and or tax attorney.
The tax credit expired on April 30th, so this will not affect your upcoming transaction. If you did indeed find a local agent to represent you, I would suggest contacting him as soon as possible to make sure he is able to be part of the transaction. If you have already found your dream home though another agent, your agent may not be honored by the other agent and you may actually not get the representation that you want. Representation, at least here in Ohio is a tricky thing, so for your sake, make sure you get someone to represent your best interests. Good luck.
Do you want to pay too much for your dream home?
Do you want to get the very best deal possible?
Wouldn't it bother you if, after you bought your home, you found another home, close by, that was on the market, but you didn't know about it?
Talk with your Realtor and go through the questions:
Why should I select you to be my Realtor?
What can you do for me that others cannot?
Tell me about how you have helped other people?
May I call them?
A good Realtor will save you time, stress, and money.
A wise buyer puts together a "team" to help and guide through the home buying process.
Part of your team should include:
Realtor, closing attorney, mortgage professional, home inpsector, and insurance agent.
With regard to your question about the first-time buyer credit - you'll want to consult with your mortgage agent, closing attorney and perhaps your tax professional. This team will help you to understand what will be in your best interest. It's possible, that while you might have the cash to pay in full, there might be some advantages tax wise to financed part of it -- tax write offs...etc. By exploring your options with your team of professionals, you'll feel more confident in your decision.