I was having huge problems with fraud on my website also. A lot of stolen credit cards being used from Vietnam. Using Braintree as my processor, I send an auth

I was having huge problems with fraud on my website also. A lot of stolen credit cards being used from Vietnam. Using Braintree as my processor, I send an authorization request for the card. If the auth is successful, I send the data over to MinFraud for a check. If the fraud value is < 25 then I submit the auth for settlement, otherwise it gets voided and the user gets a message that their purchase didn't pass our fraud check. I also log all minChecks and I manually check any request that has a value > 10 or so just to make sure it looks legit. The biggest change I had to make to support this is that I had to add Country, City, and Region (State) boxes to my payment form. So user's have to put in 3 more pieces of information that they didn't have to with a plain (a la Stripe Purchase button) payment form. However, that information has saved me from numerous frauds. Also, it appears that once the fraudsters determined that they couldn't use my site anymore, they've stopped trying. I am VERY happy with their service and it's very inexpensive.