The Harborstone Credit Union is a auto loan from Harborstone Credit Union. The ongoing APR is as low as 5.99% APR (auto, new and used). Trade in the constant repairs for a ride that actually gets the job done. Whether you're upgrading the daily driver, buying an RV to be your mobile living room or saving cash by ditching a high-interest bank loan, we make the money part easy. Options for how you travel. Choose financing for autos, boats, motorcycles, RVs and other recreational vehicles.