There's nothing inherently wrong with using WIFI for your streamer as long as the WIFI is consistent and can sustain bandwidth suitable for streaming audio (which really isn't that demanding).
You can get a wifi extender with a hard-wire port on it (to connect to your streamer) for $50, probably cheaper.
I stream hi-res audio, and 4k video over mine in a detached garage, with nary a hick-up.