Sales are a different fee and quite frankly there sales info is not very good.The 80 is for your listings to show for everyone and e-mail features and to show all available properties.
As far as research goes
http://www.costar.com is the the bomb but VERY expensive per month.You can click on a building and whether it was recently for sale or not it will give you the info on the last sale,who owns it,and phone number information,even if they are hiding behind a trust or corporation.It will also show exact rents for each building say in a shopping center.
For selling your listing
http://www.loopnet.com is really strong.For research on buying and locating things
http://www.costar.com is incredible in what it offers.Try and talk your broker into carrying it.