This game is difficult as the conversion rates can be lower than Adsense (2%) click through rates so traffic is key i.e. a good natural ranking in the SERPs.

However, there are benefits to selling leads. Some markets, such as dental insurance and landlord insurance, can be profitable and when selling leads you are pretty much immune from invalid clicks that can result in account terminations, which regularly happens with Adsense accounts.

If you have the time, ability and confidence to take on the big boys in these areas and compete then it can be extremely profitable, with some lead purchasers paying up to £100 per valid lead!

Good luck with your persuits,

Khalid.