[Technology] Experiences sought on book buying websites / apps

Does anyone have any experiences selling books to these online companies? I get that they are the webuyanycar of the book world but there seems to be quite a few of them about.

I have briefly tried the "webuybooks" app and had about a 5% hit rate on what they would accept.

I'm sure I read somewhere ages ago that some sites claim to never receive the parcel or downgrade valuations once received but as this was a while ago and perhaps these sites no longer exist?

Any past experiences welcomed - thankis.

I got scammed by one a few years ago. They offered me a decent price for my vintage jazz mags.

Never got any money as apparently their condition was ‘too soiled’...

I miss my bongo mag collection.