The useful split here is not brand. It is whether a piece is bought to wear often or bought for one occasion.
What moves the number
Occasion or everyday, which decides the size of the room.
Fabric and work — embroidery, beading, zari, and whether it is intact.
Condition at the lining, underarms and hems.
Measurements, flat, and how much seam allowance is left, because that decides whether a piece can be altered to fit.
Alterations already made.
Why two of the same differ
One listing turned the lining out and measured the bust on camera. The other showed the dress on a hanger. Describing womenswear.
How to find out rather than guess
Compare completed sales at the same measurements and condition, and separate occasion pieces from everyday ones before comparing anything.
For ethnic and occasion wear, the saree guide covers weave and zari, which carry more of the value than the label does.
When a lot beats singles
For everyday pieces, when the lot is one size. Occasion pieces almost always run better alone, with time on camera for the questions.
Questions people ask
Does a torn lining ruin a dress?
No, and it must be declared. Linings fail first and buyers in this category know it.
Are missing stones a big deduction?
Count them, show them, price for them. Unmentioned, they are a return.
Is dry-cleaning worth it before selling?
For occasion wear usually yes, and say that you did.
More: pricing womenswear, selling womenswear.