Hopefully I've read the FAQ correctly, and this is one of the shopping related questions that is allowed... Note that I'm not after recommendations of where to go, but instead information on how to work out what the right option for any situation is.
I've got a trip to India coming up shortly, and I'll be away for almost a fortnight. While I'm there, I'm thinking of getting some smart clothes tailor made. (Several friends have recommended doing so, and I could use a new suit and shirts). It looks like the place I'm going does have some tailors, even if it isn't quite so well known for tailoring as some other parts of Asia. Hopefully with a fortnight, there's enough time to find somewhere, get measured, and have things made.
However, buying off the rack is often bad enough for me, so I'm feeling a little out of my depth. What should I be thinking about beforehand? What should I be doing to help pick out somewhere good to use? And what do I need to bear in mind when buying?
(In case it matters, I'll be in Bangalore for this trip, but general tips on India would probably be good to help other people out in the future!