I highly recommend an inspection on a new home. Too many times, I have seen crews blow and go, and make not only structural errors, but electrical errors. These too many times, are hard to find as someone that is not professionally trained. Municipal inspectors don't spend near the amount of time that a personally hired inspector will spend in the home. I highly recommend an inspection.
As to having an attorney. If it is for the sole purpose of representation, then you need a Realtor. It never hurts to have a real estate attorney on stand by, as they can help you understand the contract and see if it is fair. Although, builder are not regulated like Realtors are, it would be up to you, with the help of your Realtor to get the contract changed. Purchasing a home from a builder without your own representation, is like buying a resell where the sellers Realtor, handles both the buy and sell portion of the transaction. Their allegiance is to the seller (Builder). You need someone in your corner, making sure you are not over paying, making sure the builders contract is not heavily weighted in their favor, and making sure you get what was in the contract.