Such association may purchase, hold, lease and convey real estate or stock for the following purposes and no others:
(1) Such real estate as it may need to occupy as a place of business;
(2) Such as shall in good faith be conveyed to it in satisfaction of debts contracted in the ordinary course of business;
(3) Such as it shall purchase at sales under judgments, decrees or mortgages held by the association, or shall purchase in good faith to secure debts due;
(4) Such as it shall in good faith acquire as a part of the consideration for the sale or exchange of real estate owned by it;
(5) Such as shall be acquired in salvaging the value of property owned by the association; and
(6) Such as is permitted building and loan service corporations under section 8-320.01. Nothing in this section shall be construed to forbid the mortgaging of real estate to such associations.