Buy only exclusive SEO leads. If the leads sold by your SEO company are not exclusive and if the same leads are sold to multiple people then your conversion rates will be compromised very badly. You should always insist on exclusive leads.

Always purchase your SEO leads from well-established and reputed. This is very important because reputed companies will be keen on satisfying you with their service because they would not like to jeopardize their reputation. So you ensure good services to yourself by choosing a reputed SEO company. Secondly, a company could enjoy good reputation only by delivering consistently good services. This again vouches for the quality of the services that you could expect from your service provider.

If any of the SEO leads supplied by your SEO leads company is bad, then contact them immediately for a replacement. Do not hesitate to contact them. You have paid the company under the goodwill that they will supply you with good leads that you could use and benefit. If they fail to meet the expected standards in this regard then it is your right to ask for replacements. This is where working with reputed SEO leads companies proves to be very important. 

They will not only supply you with good quality leads but they will also be quick to replace if by any chance you happen to get a bad lead.
Keep these basic factors in mind when you are buying your SEO leads so that you will be able to get the best value for your money.