No provision in a retail installment contract under which, in the absence of the buyer’s default, the holder may, arbitrarily and without reasonable cause, accelerate the maturity of any part or all of the amount owing thereunder is enforceable.
     No provision in a retail installment contract relieving the seller from liability for any remedies provided by law which the buyer may have against the seller is enforceable.
     No provision in a retail installment contract purporting to waive any of the provisions of this Act is enforceable.