Ask questions and get answers from experienced industry professionals
You can proform both jobs at the same time if you are good at what you do. I have in the past grinded a Grove in the brick chimney all four sides then used a brake to bend a little half inch lip on the top of my flashing metal flashing into massonary Grove then caulked you will never ever have to worry about again in your lifetime Only reason I did massonary work first is because I didn't want to get my shingles all dusted.