Below are two pictures. Photo 1. An enhanced screen capture of the writing above the door, shown by the black light. Photo 2 - An attempt to visualize each 'letter' or 'symbol'. From some brief research I discovered the following, the writing may be a blessing of the house. I have copied and pasted the following from a website. A traditional way of doing this is to use chalk to write above the home’s entrance, 20 + C + M + B + 16. The letters C, M, B have two meanings. They are the initials of the traditional names of the three magi: Caspar, Melchior, and Balthazar. They also abbreviate the Latin words Christus mansionem benedicat, “May Christ bless the house.” The “+” signs represent the cross and 2016 is the year.Source - www.carmelites.net/news/chalking-door-epiphany-house-blessing-2015/ Do you think the last 'letters' could be '08' for 2008.