Playing with marble(d)s?!

I was sitting at the table and could see a gecko on the fly-screen of the lounge-room window. 

Given where I was sitting and how clearly I could see him, I knew it was a big gecko - and it is, or rather they are! 

There are two living on the outside wall of the shack, near the front door.  They are both quite camera-shy, preferring to hide under the roof flashing or behind various conduit piping than staying in the open for possible fame!  (The one in the bottom pic headed down into the gap between the iron and the wall).

We've consulted both reference reptile reference books and it is most likely that our large friends are marbled velvet geckos.  Interestingly one of our books states they grow to 110mm, the other indicated 150mm and the internet link has 180mm as the length.  Our two are somewhere between 150 and 180mm.