Affiliate Marketing Secrets

I am starting a coupon website , with coupons of local retail vendors. Since I will be receiving a fee for this as an affiliate , I want help with calculating the fees I would be charging them ? if you know as to how I can calculate the fees so it is lucrative enough for the retailers, do let me know . Thanks in advance!

I joined one company recently that provides all the coupons in a database for you, for a small fee. I like the concept and it works but I recently had problems and it’s taking very long to fix.
Can anyone recommend a company that has a coupon database that I can host on my website with my affiliate codes for a small fee……thanks.