You can do a simple google search and find many sites that talk about SFI and whether it is "legit" or not. Keep a few of these links handy! Also there are numerous testimonials that can be found across the web. If all else fails take a screen shot of your commissions page and send it to them or a picture of a check or check stub that you have received. If they still aren't convinced they can decide to do their own research.. Either way at that point it's in their hands.