Man, I remember when it FINALLY sunk in that maybe Stacy & Clinton were on to something and I started getting more stuff tailored. Before that, it was just hemming pants. They really drilled it home to me that I do not have to take the clothes the way they're offered to me on the rack; I can make it my own.
And then when I figured out not all tailors are created equal? It was like the heavens opened and angels sang hallelujah or something when I finally found THE tailor for me. The one that told me what alterations needed to be done, and how much needed to be taken out of the waist, and didn't let me bully her into not taking enough out of the waist when I went in bloated one day and thought she pinned it too tight...that shop was THE shop for me.
What slays me about how RTW is made to fit the dressmaker's dummy is that no two dressmakers use the same dummy so nobody has any sort of standardized sizing. I know Angie's on to something with her take on sizing, and it does help to know which stores just don't work for me because their dressmaker's dummy doesn't have a butt like mine or whatever. But, really, even the dressmakers' dummies aren't dummies--theyre all different too!
Now, to address the question at hand:
Worth taking to a tailor:
*If it just needs the legs or sleeves shortened
*If it needs a little volume taken out by adding darts or taking in side seams, like the lower half of shirts that have to be bought to cover a chest, or the waistband of MY pants that have to be bought to fit my arse and then wind up too big in the waist
*If it is sleeveless and taking some fabric out of the straps will make it fit better (like Janet mentioned)
*Having a taper added to pants legs might be worth it
Definitely not worth taking to a tailor:
*If the rise is too high, don't take it to a tailor to have it lowered. Especially if there are pockets and zips and such involved. That's rebuilding the whole damn pair of pants right there.
*If it needs to be let out because it's too tight, probably not worth it because soooo many modern garments don't have seam allowances that make that possible
*If there isn't generous allowance in the hem of skirt or pants, they can't make it longer.
Subjective, might be worth it to some but not to others:
*Removing shoulder pads that are sandwiched between the outer layer and lining of a garment. Once that shoulder pad comes out, the way the garment fits is probably going to change, meaning that the sleeves have to be adjusted at the shoulders. Gets spendy. Was worth it for a dreamy Dana Buchman jacket (not the Kohl's stuff, the mainline stuff) that I found for under $10 at a thrift shop
*Removing sleeves can be worth it if you know you'll wear it. I did this to an Armani jacket (sleeves were a wee tiny bit constricting but not bad enough to be noticeable or uncomfortable), thinking I'd wear it. Wrong. I wound up letting it languish in my closet for years before I finally passed it on.
*If I'm in between sizes, sometimes it's worth it to buy the bigger size and have the voluminous parts taken in. This is especially true if it's a great blazer or other investment staple piece that will get worn frequently (like a dress that has to be bought a size bigger because the top or bottom half is not the same size as the other half)
*Knits/sweaters: some thinner knit sweaters might be alterable. Chunky ones, not so much.
*Leather jackets/skirts/etc: potentially alterable, if the leather is thin and there's somebody qualified in your area to do the alterations
I'm also going to throw this out there. My shoe guy made some adjustments to shoes and bags that made them wearable: adding holes to straps that were too tight, adjusting the length of a strap/handle on a bag, repairing zippers on bags, and some shoes repair shops are also leather repair shops, and they can potentially deal with thicker/sturdier leathers.
