Well, first and foremost we do need to say, this is NOT the first time we have successfully set up and online store, or had our first sale online. In fact, we have been doing it for about 10 years now. This is however, the first time we have both hosted our own site and our own eComm store.
On the developer's side, the 3rd party integration was usually clunky and time consuming, too. Sometimes, responsiveness was lost. Nearly always there were design aspects that had to be shoe horned in to fit, since they we usually set up in 2 different environments. This made usability for everyone more difficult than it needed to be and time consuming.