It is quite possible to make good money on antique or even vintage items. You can look at auctions such as
Antiqon to see which items make a profit. If you have something vintage, sell it now and don't get any ideas for the future. Because what has no value now is unlikely to become valuable and increase in value in the near future. Unless you have to wait a hundred years, and this is not a good idea. So feel free to sell antiques.