I do reality checks when I'm awake but I've never done one in my dreams, whenever I go lucid it appears to be for no reason other than I notice that something doens't seem normal. My cell phone was the case in my first real good one, it gave me really strange messages.

The checks that I use are electrical appliances like my phone. My computer is always right next to my bed so I look at the clock. If it says 4 am and I can see the sun through the window then I know that I'm dreaming.

The random places are what have sparked the rest of my dreams. A house I haven't been to in years, my grandfathers house with no recollection of how I got there... Try those instead.