My car is originally an Oriel that comes with factory wiring and retractable side mirrors. The previous owner had fitted simple ones without indicator but retraction was working in those as well because they were from a hybrid civic.
However the answer to your question: it's not that complicated, you will need a set of mirrors having retraction motor, a harness and grip for the same and a power window driver's side panel that has retraction button. Shouldn't be more than half an hour job