If offering online payment you should take note of the following risks before proceeding

• Currency Risk
  If you offer a payment method with a different currency (e.g. event in Switzerland, payment method using Euro) you carry the currency risk meaning that you might get less money if the exchange rates worsens. Of course, it might also happen the other way and you will get paid out more.
   
• Security of Payment
  If you accept wire transfer as a payment method, you do not have assurance that the participant will really transfer the amount. Even if they receive payment reminders, there is always a percentage that does not pay which leads to additional effort during the event. Transfer has its charms when there is a high entry fee as the fees are independent from the entry fee. However, there is also loss of money as participants register for the event, never pay and then do not take part, for example due to illness.
   
• Chargeback Risk
  Depending on the payment method, there is the risk involved that the money might be charged back. This might happen quite easily with direct debit - a short call to the bank is sufficient. The same might happen with credit card payments - a chargeback is possible but it demands more effort from the participant. If you allow a direct debit in the future, the likelihood of chargebacks will also rise.