I finally did it! This was an old big box of our washing machine, stored about more than a year ago. At first the idea is a house, then after browsing several ideas on pinterest, finally we decided to make a hamburger/merienda/hotdog store. I had to put first white coat (my husband refuses to use spray paint because of the smell), but instead I had to use lates for the base. 

I did not finish this in one sitting: cutting was done 2 weekends, then color after a week and then add a few touches of art paper and some print outs of bricks and names. We all use scrap materials, whatever we can find and recycle at home. Well they helped also because they are both excited to play with it.

By the way, it's also foldable for easy storage. :)