long time lurker, 1st time poster here. When looking for suits/blazers offered in the B&S section (or Ebay), how much room do I--or my tailor--have to work with, specifically across the shoulders? I'm a slender guy & measure 18.75 from shoulder-to-shoulder on all 3 of my Canali suits. Would a skilled tailor be able to let out fabric in the back of a jacket that's 18.0 or 18.25? Or is that really too much of an adjustment adversely affecting the position of the armholes? Thanks for any tips or info the only place there "may" be any cloth available is at the center back seam. how much good that will do you i dont know, but it does not seem likely. go with a size that feels right in the shoulders to begin with.