Infographic commissions very widely in terms of investment. The length, complexity, desired graphic style, amount of reviews and revisions a client desires, plus client budget - all of these factor into what design approach is used and what your part of the investment will be.
Do you have photos and graphics already? Do you have ideas on how you want the statistics to display? The more legwork you've done, the less is on my plate. I LOVE doing research and concept development, too, but I'm gonna have to charge for it, silly. :)
If you'd like to discuss your project, scroll to the bottom of the page and set up a free 15 minute quickie consult call; you're also welcome to scroll down through some examples, beginning with the more complex visuals I created while playing designed and Media Network Site Manager with Pet360 Media (now part of PetSmart/Chewy) outside of Philadelphia, and ending with a couple of simpler graphics I've created to display stats for WE-cycle.