"Closing Costs" is a general term that lumps several fees into a bundle to describe the cost to buy or sell a home. A Good Faith Estimate would itemize each of the fees for the buyer.
Typical among the costs are Title, Escrow, Loan Origination, Recording, Appraisal, Wire Transfer, Credit Report, Flood Certification, Underwriting or Lender Acquisition Fee. The majority of these costs are dependent on the companies that provide them.
Title Company A will set their charges different for the same loan amount than Title Company B. You can shop these, and usually by combining Title & Escrow reduce the total a bit, but I've not seen them "negotiate" their structured fees.
Lender Origination is up to the loan officer and may be negotiable. The loan originator will be paid a fee either from the borrower or the providing lender's rebate that comes from delivering a slightly higher rate. Most of the other third party fees are fairly common and set by the companyâ€™s involved.
Pre-Paids, which are in addition to closing costs, are non-negotiable for the most part. These fees include your first year of Home Owners Insurance, setting up your property tax and insurance escrow accounts with 2-6 months of payments and the daily interest from when you close until the end of the month.