I understand your concern. You want to net the most money when the deal is done, and you are afraid that paying a Realtor's commission will hurt too much.
Studies have shown that Realtors generate higher selling prices and less hassles than selling "FSBO".
That being said, the FSBO sites you are referring to are cheaper but provide very few services, and it is probable that you will still pay the selling Realtor her full commission.
Studies have also shown that buyers understand that FSBO sellers have no one representing them, and are likely to offer much less than the listed price.
The forms you asked about, the Buyer Synopsis Report is available thru the MLS -- which means the home has to be listed by a Realtor -- while Property Disclosure report is free and available online or from a title company.
You definitely should use a title company for the closing. There are just too many areas in which a mistake would be very costly.