Does it cost the same every day is there a good discount

You could probably call and ask them for a discount, especially during low times at Disneyland (kids in school, extremely cold weather, etc.,). You could also ask for military, police or firefighter discounts. It never hurts to ask.

just like any other hotel. There are always cheaper rates though, through diferent search engines

Prices vary just like all hotels.

Prices will vary.