The use of a third party system for payment would be an ideal thing to do, but if you can really manage your payments online, on your site, it’s not an issue. I would only recommend a precaution of purchasing an SSL certificate for your site that will enable secure web communication for the payment transfer and also enable a professional look for the site. I would recommend
SSL Star for the certificates as they have a wide range and you can get good price deals on trusted providers like Thawte, Verisign and GeoTrust to name a few.