When we bought our first property in CA we had to educate ourselves. Real Estate in the Netherlands is totally different, it has more resemblance to what is customary on the east coast. The purchase agreement is different in every state and they change from time to time. Last week we had an official training in our office to go over all the changes in the new purchase agreement we use in California. The last time this agreement changed so much was 17 years ago.
The new agreement is 10 pages long, the changes reflect recent changes in law as well as feedback from the industry. The program used by Realtors to fill this out, automatically adds forms as needed. Here is a sample draft : new RPA draft
I see quit often that a purchase agreement is filled out in a rush: at the end of a day of looking at properties. Everyone is tired, there is no time to go over the offer at length. Much better for any buyer is to go over the standard agreement beforehand and discuss questions and details that reflect specific needs before making an offer. Personally I give every buyer a Buyer’s Guide for our area the moment we discuss the plans to purchase property. Besides other good information, there is a copy of a current purchase agreement and other forms that are normally used as well as the local general disclosures. This copy can be studied/highlighted so I can answer any questions. 
There are many important details that need to be decided upon when buying a home. It is important to address these before making an offer, not in a rush while preparing the offer.
Mirjam