Sometimes Reverb users will see their bank or credit card issuer list purchases or billing charges on Reverb as "recurring", however: this is not a recurring charge.
Reverb makes it safe and convenient for users to store their card information on Reverb for future purchases and billing purposes. In turn, some financial institutions make the assumption that the charge is recurring, even though it is not. These "recurring" statement lines will typically drop off in 24-48 hours.
As always, it's totally free to list your gear, and you only pay a 5% selling fee if your item sells.