For me I would have to suggest the PayPal route. This is even more evident when you administer your own web sites as you control exactly what is on screen not the 3rd Part software that runs your cart. PayPal is a good starter - lower rates etc. Once established then consider upgrading to someone like WorldPay, I have used them in the past and they are good - but if you margins are low then don't rush into anything with them. Tip - Keep it simple at first and develop your payment methods over time!