I know there are mixed opinions on Whatnot but I have been on there since January with great results and there is a nice, small but tight-knit vintage community on there.
Tomorrow (Monday 9/25) at 5 PM Eastern I have an absolutely ridiculous vintage baseball show on Whatnot. E98 Cy Young, T206 Addie Joss, 1938 Goudey Hank Greenberg, multiple Mantles, and more all starting for auction at $1. Each auction runs for 15 seconds with no sudden death, so the clock resets to 0:10 each time a bid is placed.
Hope you will check it out!
https://whatnot.com/s/f6Hjs0Bw