RX Vega 56 and 64 have been around for a long time now, are there people still building rigs with these graphic cards? Since they are now old AMD cards I expect them to be cheaper right now, also are they still Profitable for a certain algorithm?
You've missed the buying opportunity period, now is not a good time to buy any graphics card, even old graphic cards that aren't good for mining have increase in price, you have to wait for find ways to get MSRP price which I'm sure that you can't.