In addition to what Fabulassie has said, can you be specific about this 'guarantee', please? Is this a money back guarantee, and if so what are the terms? Are you saying that we will get X amount more bookings or earn X amount more money in X amount of time as a direct result of advertising on this site, and if so, how are you/we to prove it?
Secondly, some more information about this 'database of paying customers', please. If you have been obtaining and storing punters' details I'm fairly sure they would like to know about it, and we'd all like to know where you got them and from whom? How this database is maintained and who has access to it would be good too.
In your own time.