Sometimes… but most Builders do not allow this because:
1.) for appraisal purposes they need to protect their price point in the community where they are building and selling.
2.) It creates extra time consuming paperwork for the Builder’s contract department
and also for the Lender, who has to make sure that the contract modifications will conform to the loan program. Lenders sometimes frown on the practice. There is sometimes more Builder flexibility in the lower priced New Homes where FHA financing is being used and there is more NEED and tolerance for contract modifications and higher closing cost contributions.
NOTE: ALL of the Builders allow and cooperate with the Realtor making a closing cost contribution to the Buyer when it is Lender permitted and necessary to get the deal done.