Proceeds from the sales of lots and personal property not invested as hereinafter provided shall be applied solely to pay debts incurred in purchasing cemetery grounds and property, to fence, improve, and beautify the grounds and the avenues leading to the grounds, and to defray the necessary expenses of their management and care. Real or personal property given to an association to maintain a monument or to keep or improve grounds within the cemetery must always be applied to the uses for which the property was given.