I have attended a few MicroConf's where patio11 is a regular speaker, and from his "selling BCC" talk it sounded like feinternational will help you figure out if it is a good deal to work with them.
What's to loose other than a few hours of work filling out their questionaire about your business?
I will be careful about SOLD listings there. They never list the actual selling price but only the asking price. So you don't know what the final sale price was.