WiFi or Bluetooth? I Think I Had A Brain Spasm!

So I'm building this basement system with mostly vintage stuff from eBay and the like. So when I bought the receiver (Marantz SR4500) I simply forgot that it is neither BT or WiFi capable. So I found on Amazon a BT receiver from Logitech that would make it work, like $30. Spent more on the connecting cable knowing that it still would probably suck. Then I submitted a post asking whether one of those Amazon Echo Links would be a worthwhile improvement over the Logitech or not. The whole time not realizing that I have great WiFi in the house, and that WiFi is another, perhaps better, option. So the question is, IS IT? And if so, what to buy? Where to buy? Basically, how to do it. I confess ignorance on this one. Thanks for any input. Much appreciated.