You can find many differant kinds of accommodation in Ulaanbaatar city, s all staying from 7 USD guesthouses to 5 star large and fance hotels that may cost over 120 per night. They are all quite busy in the summer time from May to October and largely empty in the winter. They cheap guesthouses are usually located in former apartments with 4-6 beds in one room. They have a kitchen and serve breakfast, internet access, laundry and tour arrangement services. There are cheap and comfortable enough for those who are interested in authentic or rough traveling. There are 2-5 star hotels in the city and you van find hotels with excellent service. You should note that not all hotels can meet your good expectations. 

For instance, once or twice every summer the hot water supply may cease for annual repair works made at he power centrals. All 3 and 4 star hotels have English speaking staff but still, at many hotels only a few staff may be able to speak Englsih.