High value items - tips!

Having a big clear out and sold a lot of stuff over the year - all relatively low value (highest was around £55) however my last few bits to sell are some designer items that would probably be between £150 and £300. I know lots of people say not to use Vinted but the so called designer resell alternatives don’t seem to be any better in terms of customer service and I at least have a profile on Vinted with 250+ positive reviews. Any tips for selling high value items on here? Or any other platforms I should try? Thx