A negative database full of numbers that have charged back transactions can be useful in identifying possible risks. These databases can be updated online. A contract with a credit card verification service, such as CyberSource, that can perform a host of checks for each transaction, such as checking the IP address, real address, time of day and other factors to create a profile and build a numeric confidence rating for the credit card. One thing to factor in when considering security risks is where the information is residing. Consider the security precautions not only for when the information is in transit, but for where it is stored, and who may have access to it.
Cost creates another set of risks for online payment systems.
When choosing a bank for an Internet merchant account or a commerce engine for clearing services, make sure to ask for the complete cost of the service. Some companies will quote a list of fees, but will not mention other costs involved. Dig deep and find out all fees involved. All of these services cost money, and you have to factor in the cost of your online payment system into your overall business plan. Don't expect to make a lot of money right away, not without some targeted promotion.