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. 
Well even though you have wifi you still need something to read it and translate to an audio signal for the amp.
I guess depending on what you are streaming there are two relatively cheap options.
Google Chromecast Audio streamer.
Bluesound Node streamer.
Both will work on Wi-Fi, both will send an analog RCA output to your receiver.
Both can be controlled by an app on phone or tablet.
Really depends on what you are streaming as to which might be best option on the cheap.
One thing I really like about the Chromecast is it is tiny and you can hide it behind the receiver so keeping that vintage appearance vibe.
Either option should be a lot better SQ than a bt receiver.
What is your budget I guess?
If you are using Apple products, you can get an old Airport Express from Apple (~$20 on eBay, used) to use AirPlay. Unlike BT, AirPlay is lossless. Check this article if you are interested. GL.