If I sell clothing, it's sports jackets (Lakers, etc) and they are usually extra clean. Sometimes I will try them on eBay first, sometimes not. If they are the kind that sell for $100 at the store I usually ask $40 and stick to it.
I only sell new T-Shirts (ones that have never been worn) and depending on the design I ask $2 to $4.
I sell uniform jackets, pants, etc. A used olive colored jacket with fur collar worn by some police, etc goes for $80 new and again I ask $40 and go from there.
Jeans, for me they have to be Levis. New with tags I get $15 and stick to that price. They don't want to pay it, someone else will. Used Levis, $5 to $8. Again I stick with the prices.
All other clothing (unless double deluxe) goes in black garbage bags and sells by the bag to the clothing lady across from me for $5 a bag. She can make $40 or more, but I don't have to hang them, sort them (possibly clean them) etc.
My best sale was probably a crew jacket (from a movie crew) for an Industrial Light and Magic film...don't remember the title. Got $100 for that on eBay.
Name brand sneakers (Nike, Vans, etc) usually $20 to $30 if they are $60 to $80 shoes. Best was $70 (or so) for a pair of green Fighting Irish shoes...on eBay.
Hope this helps.