When your Realtor writes an offer for a property for you, have them ask for up to 3% in closing costs from the seller. Some sellers will agree to this and some won't. Most bank owned homes and short sales won't - but I've had a few that have. All you can do is ask.
When you make up your offer for the house,
include that the Seller will allow 3% for Closing Costs in the deal.
Your Buyer's Agent will know how to do this.
He'll also remind you about including Contingencies for the Loan, the Inspections and the Appraisal; he'll explain how and why.
Good luck and may God bless