Typically builders have a preferred lender, and if a Buyer uses this lender, you will have some of your closing costs paid. The most recent contract with a builder was giving $7500 towards closing costs.
Be sure to ask what their current interest rate is, and approximately what their fees will be. Also, call another lender (maybe the REALTOR's suggestion) and get another estimate to know whether you want to go with the Builder's lender or not.
I went over the LE (Loan Estimate) with my Buyers, and they sure add a bunch of what we (REALTORS) call junk fees. Most of my lenders do not charge an origination fee or processing fees.
Buying a brand new home from a Builder, you will be paying fees you normally would not pay if buying a resale home.
In the end, my Buyers did stay with the Builder's lender, the rate was lower and so was the overall costs.