NOT to buy. And that's exactly what we're trying to avoid. I don't mean to imply that you should have NO free information on your site, but use it in moderation. And, let whatever freebies you DO offer be a means of leading to income for yourself. For example, if you have an extensive library of self-authored articles, offer reprint rights to those, and add to it regularly.
Online marketing is all about testing, and there's no harm in trying new strategies.
If you don't know, let author Harmony Major show you today, for free.