Read the whole thing

You should have gotten 80% of the work and evaluation from the previous scans, but now it is time to go through the whole document.  As you get more experience you can skim some of the sections, but if you are starting out we recommend reading every word.
The pieces of a solicitation: A solicitation is typically composed of:
1) An abstract: This is the text published on SAM.gov.  Sometimes it’s missing, sometimes they put in everything.  But best case the abstract provides a concise summary of the requirements in the solicitation.
2) The Solicitation: This document contains the Statement of Work and the administrative information, like the evaluation criteria, or the payment schedule the government plans to follow.
3) Amendments: The government edits and updates the documents all the time, and when they do they release an amendment
4) Attachments: If the government has detailed information about a particular subject they may publish an attachment that focuses on that topic.
5) Combined or separate documents: The Government may combine everything into a single document, or it might be split into a dozen separate volumes.  Either way you need to engage with everything. 
You are responsible for changes: I have MANY friends who’ve poured hundreds of hours into a proposal, and had it rejected because they used an old version of the solicitation.  YOU HAVE TO MAKE SURE THAT YOU ARE USING THE LATEST VERSION DOCUMENTS.