How to set the right price for leads to clients?

Depends on what type of leads you have and what industry (consumer/business etc), just phone numbers with names or their complete details, email adds and so forth.. There are companies out there who sell leads for like $200 to $500 (10k / 20k / 30k leads).

If you generated them yourself and know that each one are genuine and working then you give your price... realistically, I dont think people would pay a dollar per lead unless they are warm leads already.

If you've pulled it out from somewhere (raw leads) then you got to give it a whole sale price.

Hope that helps.