Hotel prices in Strasbourg (outside of the pre-Christmas time when they are high all the time) can vary drastically depending on whether the European Parliament or the Council of Europe (or both) are in session or not. If they are, it can be punishing. Otherwise, there can be lots of small independent hotels with a lot of charm and and very decent comfort. It's a nice city and (in my view at least) the food is great. Enjoy!