The crown is what keeps water from entering in-between your bricks/blocks/stones and the flue liner area. In general, crowns deteriorate as the years go on and I'd love to help see if I can give you a hand. My crowns are not rushed and I aim to make a day of it to reduce the chances of wind or sun curing it too fast, because of an all day gameplan, I can not compete with a 3-5 hour visit with maybe never returning to see how it cured. New crowns can lift and crack! Please keep that in mind :( I want to help prevent a cheap route that can be flushing money away if they it does not go well. On to the brass tax, prices vary, contact me for details.