I am evaluating RFID tags for a project, and would like to minimize the cost of the tags. We can find UHF (EPC Gen 2) tags for much less than HF (Mifare UL) tags. Unfortunately, the least expensive reader/writer module I could find for UHF tags is about $200, whereas the least expensive module for HF tags is closer to $20.
Are there any less expensive (< $50) UHF RFID reader/writer modules available? Is there something inherent in the UHF band that makes it more expensive to build an RFID reader/writer module?