Am I selling things for too little?

I'm going through a pile of clothes my mum wants to get rid of, what i've put on is mostly clothes from low cost fast fashion brands such as primark and shein. She says £1-2 is far too low to sell some of the clothes (mostly womens summer dresses) but i dont agree. The most ive put something on for is 3.50 and it was new with tags. My idea is that if theyre just going to sit unused in a wardrobe or go to the charity bin anyway, whats the harm in selling them for cheap?

What do you guys think?