Dear Customer (name blocked for privacy),
If your agreement was to only allow them to borrow your credit, and they are the ones who got the benefit of the skis, then you can likely (nothing is ever 100% in court) succeed in small claims.
Normally, as you say you sold the skis at a loss, you will be able to claim from the court the amount of money you paid the banks, including likely any late fees or penalties, less the amount you sold the skis for.
PLEASE NOTE: Responses here are for information/education only, NOT legal advice and do not form attorney-client relationship! Only licensed attorneys you hire in your state can provide legal advice.