Seoul has been a great attraction for a long time: it is interesting for both lovers of active sightseeing and those, who love it slow, including travellers with kids. This is why hotels in Seoul are really well developed and keep getting better.
Apart from luxury hotels, some of which are famous for their rich history, Seoul has to offer more affordable hotels and hostels, and those are sometimes not less nice, due to modern interiors, freshly done renovations and distance from noisy locations. Although, it is challenge now to find a hotel in Seoul with no Wi-Fi connection or clean towels.
The hotel prices in Seoul are defined by several parameters. First, this is living conditions: you may want to choose a presidential suite or an eight-bed room in a hostel. Second, it's the location: the closer the hotel is to the city centre, the more expensive the room is. Third, it's the season. Summer is usually the high season for travellers and Seoul is no exception. Good hotels in Seoul run out of cheap rooms very quickly, which is why if you need an affordable room, you need to take care of it in advance.
In order to avoid mistakes, read some comments: Seasoned travellers will highlight upsides and downsides of certain places, give an advice how to book the room cheaper and help choose from a variety of hotels in Seoul.
If you want a convenient accommodation that does not cost a fortune, you might want to choose a hotel 15 to 20 minutes away driving from the historical centre. This way you save on expenses and still guarantee you're accommodation is comfortable. Besides, walks to the hotel will allow you to go away from trivial, crowded sights and have a look at Seoul from a new angle.