I'm trying to gauge interest in a potential group order of the open-source, low-cost ETag RFID readers designed by Eli Bridge's group. More info here on the readers https://www.wildlabs.net/community/thread/762
Eli shared files (https://github.com/Eli-S-Bridge/ETAG_V10) to build the reader, or have it built. Orders of small numbers of reader are expensive but, because of economies of scale, the reader becomes very affordable when ordered in large quantities: for instance, ordering ~300 readers brings the price down to ~USD 30 (from ~USD 125 for 10 readers).
Just like for the famous Audiomoth, a campaign could be started on GroupGets.com.
If you are interested, let us know how many readers you're likely to want (let's consider an estimated price of USD 50 for now). You can send me a personal message too.