The value of vintage clothing and accessories depends on several factors like age, condition, quality of materials (composition) and how it was made, if it is by a luxury brand or not, the list goes on.
Long story short, all vintage isn’t valuable. Here is a list of aspects affecting the value of vintage items, many of which has the same influence on second hand and premium second hand items too.
Is the brand, model or specific item in demand right now?
If vintage items go into fashion once more, their value can increase drastically. Just consider the Dior Saddle bag. Some would argue it isn’t a vintage item just yet, but the same logic applies. It was iconic back in the 2000’s, to be almost forgotten and selling for next to nothing on second hand marketplaces until 2018 when it through clever marketing from Dior became one of the most sought after handbags that year, and it still has great re-sale value.
Is the item rare or hard to find?
This one is pretty self explanatory. It’s all about supply and demand.
How old is the item?
Usually, older items comes with larger price tags, but this all depends on other aspects like brand, size and condition. Current trends also play a part in this, as we can see with the current interest in 80s fashion making defining pieces from that era sell for significantly more money than they did just a couple of years ago. Generally though, timeless designer pieces keep their worth, or can even increase in price (like in the case of classic Hermès and Chanel bags for example).
What’s the condition of the item?
This one is pretty straight forward. An item in good condition is more valuable than one in poor condition. Generally though, we accept more flaws the older a garment or accessory is.
Whats the quality of the item?
A handmade purse with no label could fetch a larger price than a brand name one of lesser quality. Rare and/or luxurious materials of high quality, like cashmere, silk, rare or exotic leathers, influence the second hand price tag. As does the quality of the stitching and hardware being used, when applicable.
Is the size popular?
This applies for both clothes and accessories like shoes and bags. If the size is common, the item has a larger pool of potential buyers, increasing the chance of multiple people being interested and increasing the demand/value of the item.
Further reading
SammyDVintage have posted an article on The 7 secrets of how to price vintage.
Dustyoldthing.com have written a blog post listing 9 Types of valuable vintage items.
Fruit Cocktail Collectibles have a post on How to tell if vintage clothing is valuable.