According to LabCE, the test used to identify Enterococcus spp. is through bile esculin agar and 6.5% salt broth. As for the price, it depends where you live in.

Ref: https://www.labce.com/spg1142287_identification_of_enterococcus_species_from_clinic.aspx#:~:text=Presumptive%20identification%3A%20Growth%20on%20bile,another%20approach%20to%20presumptive%20identification.

Check this link for the price of bile esculin agar:

https://www.sigmaaldrich.com/catalog/product/sial/48300?lang=en®ion=PH

And these links for 6.5% salt broth:

https://www.keyscientific.com/6.5-NACL-BROTH-W-INDICATOR.html

https://www.amazon.com/Indicator-Tolerance-Polycarbonate-Hardy-Diagnostics/dp/B009Y2ZU46