Seconhands (Vienna)

Hello everyone,
is there anyone keen on secondhands? I miss my favorite one in the Czech Republic where you could get great pieces for almost nothing. I have seen few in Vienna but they were called "luxury" secondhand and prices were starting around Protected content . Would anyone know about a good secondhand in Vienna? There are plenty of them in London or Berlin but I guess you have to know where to look for them and so far I was not lucky in Vienna...

Thank you!
Nika