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. The seller can remove anything not permanently attached. If you have any doubt at all, write the item into the contract. Do not rely on the fact the item is listed as being for sale.