If a Guarantor fails to promptly perform his obligations under this Guaranty, the Lender may from time to time bring an action at law or in equity, or both, to compel such Guarantor to perform his obligations hereunder, and to collect in any such action compensation for all loss, cost, damage, injury and expense sustained or incurred by the Lender as a consequence of the failure of such Guarantor to perform his obligations together with interest thereon at the rate of interest applicable to the principal balance of the Loan.