Payment systems
Secure online payment systems are operated by high street banks and by specialist companies. Costs vary significantly so it's worth exploring the options.
If you have a credit card merchant account with a bank, the first step is to check the terms they are prepared to offer. Your agreement may allow you to collect the customer's card details securely on line and then process the transaction manually as a 'customer not present' transaction.
A better way is to integrate your shopping cart with the payment system provided by the bank, who may charge a monthly fee, plus a percentage on every transaction. Costs may be reduced by using a payment gateway such as Protx, which integrates with the bank and makes a fixed monthly charge.
If you don’t have a merchant account with a bank, a simple option is to use PayPal, who can set up an account almost immediately and charge about 3% per transaction.
I can help you select the most appropriate system for your application, and integrate it to create a truly effective business web site.