Oral agreements are not binding. Be sure you have carefully inspected the property condition and neighborhood. Check the schools, shopping, taxes, special assessments, homeowner's association and surrounding zoning. The time to seek legal advice is before, not after, signing. After signing the contract there is no further negotiation, so be certain you understand and agree to all of its terms.
Every word is there for a reason and carries obligations and responsibilities.
Every term is also subject to negotiation and change. The NVAR New Homes Sales Contract is not widely used. Most builders have their own Contract and they are notoriously one-sided. There is often no fixed delivery date, the builder reserves the right to change landscaping and materials without notifying you and the contract may not be contingent on your ability to obtain the loan or sell your existing home. Seek legal advice before you sign.