As a customer, I found their concept of pay-per-use inconvenient. I would rather have gladly paid a little more and not have to worry about replacing bed sheet and towels, or cleaning the kitchen/apartment (the package by default does not include many services and one has to order and pay for these services) . During 8 nights of stay, our sheets and towels were only replaced once by the hotel. I had the option to order and pay extra for more frequent replacement of towels and sheets, or to do the laundry myself. In addition, I had to pay 1 Euro per day for ironing and a similar amount for access to Wifi from my room. Also, I would have appreciated 'free' breakfast with just the basics (juice, coffee, bread or cereals) - this would not cost Appart'City more than 5 Euros per customer. At the moment, breakfast is not included in the room fees. So, in short, it's all these little inconveniences that would make me think twice before I recommend anyone to the hotel. Management could easily improve these things.
Mattress was also uncomfortable.