After clicking on the Apply Campaign button on General tab of the Real Estate Contact you will be presented with the following.
A dialog box that will you can select the campaign you want to apply, when the campaign is applied the status window is displayed.
"Prefix Campaign Activities with" is used as the first part of the subject line for all the activities when the campaign is applied to a contact(s). This can be used to designate a property address or other info you may want to link to this applied activities.
