So somehow we are meant to believe Maria murdered Caz, rolled her body up in a rug and got it down the stairs and out onto the street and presumably into her car without anyone noticing? Funny as you have every nosy bastard and random character bumping into each other every 5 minutes so somebody would have noticed if this was the case.
But of course this is the Weatherfield plod, and Maria will be automatically guilty and no doubt those close to her will think she is a killer. Corrie logic at its finest.