Which is the best way to alter a suit to make it fit correctly? Tailors/seamstress please help!?

Question

I am buying my brother a suit for my wedding to match the groom as he is an usher.
The suits we have seen and bought for my fiance and best man are not available in my brothers size!
From a tailor/seamstress point of view, I'd like some advice.
For the jacket - a 36 regular fits his chest but the sleeves are too short. Is it better to a) buy the 36 jacket and have the arms extended or b) buy a 38 long fitting jacket so the sleeves fit correctly and alter/take in the chest area?
Also, his trousers - he needs a 30 waist and long leg. Is it better from a tailoring point of view to a) buy the 30 waist but regular leg and have the leg extended or b) buy the correct leg length in a 32 waist and have the waist taken in.
Or does it not make a difference?! Obviously I don't want to make a hash of it because this is for my wedding so any advice as to which size to buy and have altered would be greatly appreciated. Is it better to get the larger sizes so that spare fabric is available? Thks

Answer 1

The place you buy the clothes should have an alteration service. It is always better to buy too big and have taken in, as extending the arms or legs is practically impossible.

If the store doesn't have an alteration service, go to one in the mall or the dry cleaners (which is where ours is). I have done alterations myself, but it is not easy.