Sleep on the Water
Good and cheap accommodation in Prague are the botels, they are boats on the river, next to all attractions.
I stayed at the Botel Albatross once, other ones are the Vodnik and Admiral.
You should not stay in a botel if you get dizzy easily. When you look out of the window and right onto the water it can happen that you feel like in a passing train, the water racing, or you racing LOL But you get used to it.
Botels are also quiet places, thus great for a good nights sleep.
For more just google Prague, Praha or Prag + Botel