Actor to play Witch for Halloween prank

On the 30th of October we are hosting a Halloween garden party where our guests will need to walk up the garden into a shed to collect their entry tickets. We need a lady to dress as a witch to hide nearby and give them a little scare! Will only be needed for around 2 hours but can stay and enjoy the party if they would like (Must be 18+ of course!). Must provide own costume but we will also cover the cost as well as £80 for their time.