I stayed at this hotel with my family for 2 nights in the Modern Rooms on weekdays. When we first arrived there, we were the only guests, but the next night more guests started coming in. The staff was very helpful and friendly! The rooms are clean, the beds were very comfortable, but there were small ants. I didn't have a problem with that though. The rooms are the right size for me, but if you have kids they might be a little small. Also, they gave us a fruit platter (an apple & an orange), and for every night we stayed we got two chocolate pralines.
Breakfast was great. When I stayed there the first morning, the waiter took our breakfast order (they have continental/american/indonesian). It turns out the hotel will only have a breakfast buffet if more than 7 rooms are occupied. If not, the waiter will take orders just like in a restaurant.
I really love the clubhouse, the restaurant (they have huge windows and were very Dutch) and the huge open field. It's a great place to go jogging, but there is a gym too if you prefer working out indoors. They also have a swimming pool. You can play tennis as well in the hotel (they have 3 tennis courts) but when I was there, every morning the tennis courts were always occupied, so if you want to play, I suggest you play really early in the morning unless you don't mind waiting to take turns. The location (Ciumbuleuit) is not very far from Cihampelas street if you like to shop. My parents loved the place because it was homey & located in a quiet housing complex.
I wish they had WiFi in the rooms and not just in the restaurant though. The restaurant and the hotel rooms were quite distanced. Concordia is affordable, but before you book the hotel, I suggest you contact the hotel first for their official rates. I booked this hotel through Agoda, and I paid a little more than I should. But it's not really a huge deal because it was worth the price I paid. My family will definitely be back in the future.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.