Only a formal contract of sale signed by BOTH the buyer and seller would become binding once the three day attorney review period has completed. In NJ all offers have to be presented in writing so your agent is using an a simple offer to purchase form to present your offer. You can ask him or her to add the inspection and attorney contingency to the offer to purchase. Either way, if the seller accepts your offer, formal contracts of sale will have to be drafted and signed by both parties and then submitted to the attorneys to review.
A contract of sale states an attorney review period, home inspection contingency, mortgage contingency, etc. I recommend asking your agent for a copy of a contract to review, that way when you do get an accepted offer you are familiar with the document. Your attorney will mostly adjust some of the language in the contract during the attorney review period in the form of a Rider to the seller's attorney.
All the best in your home search,
Walter J. Burns
1 Newark St.
Hoboken, NJ 07030
201-653-8488 Ext: 230