I recently found this really great tweed check at a thrift shop. It's thick but soft and has a great earthy color scheme accented by a punch of burnt orange, very British. The combination of details it carries is pretty cool too: natural American style shoulders, 3/2 front, with darts, three button cuffs and a center vent. The flap on the breast pocket is the icing on the cake. But if it's going to be mine, it will need some work.
It fits me great through the shoulders and chest, but it's a size "long" and wear a "regular". I'd need to be two inches taller at least. As you know, I'm a big proponent of utilizing the skills of a good local tailor on good clothes found through thrift, but an educated consumer also needs know what realistically can and can't be done. Obviously, the sleeves are long and shortening those would be no trouble or great expense. However, in this case, the skirt of the jacket needs to come up by about two inches. It can be done, but it's a costly job averaging between $35-$50 when done well. Still, that's not the kiss of death.
No, the decision not to alter this coat is a matter of proportion. Even if done well, shortening this coat will drastically change it's lines. The pockets will set too close to the hem, and the button stance won't look right. In back, the vent will become too shallow. A good tailor can do the work, but an excellent tailor will refuse it for these reasons. I recently came across a double breasted navy blazer by Paul Stuart at a thrift. It was obvious immediately that the coat had been shortened for all the reasons I just listed. The work had been done well, but the coat would never look right again, no matter how nice it may have been in the first place. I threw that one back.
Finding a good tailor doesn't only mean finding one who can execute your requests well, but also one who knows when to say no. Just because you can doesn't mean you should.