We were a large group of friends staying over the weekend in Katja's apartment and she arranged everything beautifully to our convenience. The house itself is great for enjoying the company of your friends and all appliances you'd want can be found. Public transport (buses) are just around the corner and takes you to the central station (~20 min) or if you ride only a few stops, within walking distance of Nyhavn and Kongens Nytorv. We had some troubles with the payment and I'd advise you to go with the phone app for travels, seems like the easiest option. Overall a great option for staying in Copenhagen!