What are the recommendations for staying in Warsaw for 2 night for a group of 4? We are planning on visiting Warsaw in mid-September.
For a more atmospheric choice, stay anywhere along the Royal Way close to the Old Town. If you want to stay in the city center, then be prepared for high-rise business hotels (Radisson, Hilton, etc.) which have amazing discounts during weekends when business travelers are not filling the rooms. I would pick the former since business hotels are the same anywhere in the world, whereas more boutique type properties are less forgettable. I stay with family when I visit, so I don't have any specific hotels to recommend. You can find lots of options on www.booking.com.
Hopefully these links will help in your planning:
http://warsawtour.pl/en (Warsaw city guide)
http://warsawtour.pl/en/brochures (downloadable Warsaw brochures in PDF format)
http://freewalkingtour.com/ (various city walking tours)
I visited Warsaw in 2015 and found the hotel prices quite cheap--so much so that I ended up staying at 2 super-fancy hotels for about $90-100 US, queen bed. I'm sure I could have stayed somewhere nice for less, but these hotels really made my stay extra-special and as a solo traveller it was worth it. I made an error in my days so spent the first night at Ma Maison Regina at the end of the New Town (which is still old and flows into the Old Town) and it was absolutely wonderful and also quiet, then 3 nights at the Hotel Bristol on Krakowskie Przedmiescie, smack dab in the midst of Old Town--gorgeous hotel from 1901, every amenity you could want and excellent front-desk staff. Both hotels had enormous, beautifully furnished and very comfortable rooms and huge bathrooms with spa tubs. Whatever your budget is, I do recommend staying in the Old Town area to be in walking distance to most sites.
I second the recommendation of Ma Maison Regina. We stayed there during our last trip to Warsaw. It's a very high quality and upscale hotel, and the rates were very low. Breakfast was included, and it was a very nice breakfast. It's a great location. You can easily walk to almost all of the main attractions in the city.
I like Novotel Warsaw Centrum. Stayed there 3 different years. Close to train station Warsaw Centralia, walk or one tram/bus stop. Easy tram ride to Old Town and ticket machines outside hotel (70 and older ride free). You can come and go to Chopin airport via bus 175. From airport the Centrum stop is right at hotel. Going to airport I use the hotel car/taxi for 60 zloty. Also in underground passage many kantors (money exchanger) at excellent rates to exchange cash. Also next to train station is Złote Tarasy a new giant mall with countless shops, movies in English, food court and other restaurants. http://zlotetarasy.pl/
A very nice option is the Chopin Boutique Hotel and the price is reasonable. Great breakfast and lovely, repurposed furniture. One funny thing: We had a very large room and I was looking for the bathroom. Oh, no! Did I get one of those old hotels where you have to share?!! I always try to be so careful when I make a reservation. Then, I opened the middle door of the large wooden wardrobe: there was the entrance to our fully modern bathroom!
Great place to stay.
This Oct. will be our first stay in Poland but we are also using Novotel Centrum. If you look at their rates be sure you put in the exact dates. There is a big price jump in September over May rates when I first booked. Accor hotel chains are tops for good web sites and phone center help/bookings/cancellations - have used various hotels in that chain for decades. Get into the Accor "club" for an additional 10% discount. Go to Google street view and look around at location. Within about 50 yards you have bus, tram, and metro service. Easy access to the Scenic part of the old town.