littletinyfish on buying tailored clothing:
…You’re supposed to get your suits tailored AFTER you buy them. They’ll sell you a suit that is “too big” so the tailor can trim them down to your size. It’s not as easy to go from small to big. Don’t trash your MW suit just yet; invest another $50…
I know it doesn’t help you this time, but next time if you’re looking for a suit give IndoChino a look. You give them measurements (taken yourself or by a tailor) and they make a suit to match those measurements. They also pay for alterations to make it right - my groomsmen and I did this for my wedding, and it turned out much higher quality (and slightly cheaper) than buying it from a retail store.