If you get it made in India or Asia this is the norm.
Long sleeved shirts from a good tailor in Saigon or Bangkok are 15-25 EUR p.P. for the tailoring. Then add 3-20 EUR for fabric – depending on what material you choose.
Once the tailor has your measurements on file you can either send your fabric of choice there and have the shirts be in your mail three weeks later or they send you pictures of fabrics they stock and you choose.
20% of my shirts are off-the-shelf (but all of them have been adjusted to fit me bette). The rest are tailor made.
100% of my trousers are tailor made. I never understood why any sane man would pay for pants that are pants (pun intended). Too tight, too low waist and too short at the ankles. It makes you look like you are the younger sibling from a poor family who inherited the clothes from the elder, taller brother. And you even paid for that eye-cancer-inducing disaster. ;)
I have a tailor in Berlin who charges 70 EUR for tailoring a pair of trousers. With fabric that means I pay less than 100 EUR usually. Which is totally competitive with off the shelf pricing. He charges 40 EUR for a new cut. Aka: if I show him a picture of a cut or photo he will make it for my measurements. This is a one-time cost though.
As an added plus I have extra pockets for change/coins and invisible pockets under the belt line which are great to stash anything pointy that will distort the shape of your leg if put into the normal pants (I e.g. put my keychain there when I go dancing tango).
And the craftsmanship (seam look/quality/longevity) is superior to anything I can buy off the shelf. Even expensive brands are commonly produced with lower quality nowadays. You pay for the better material and the brand but the seams and button stitching are still sub par.