Insurance is the best source for funding transitions which occur because of death. Gifts are seldom recommended. Bank financing, even if guaranteed by the firm, assures that the stock is something more than a valuable employee reward. Allow for identified future owners to have access to financial information. While an appraisal is an interesting snapshot in time, it may not be the best indicator of at what price stock should be bought and sold in internal transactions.
Banks are often useful in assisting in the financing of stock purchases by the younger owners.
Banks lend money based on relationships. Therefore, keep your banker informed about your business and your plans. It even helps to borrow and repay money even if such borrowing is not a necessity. Many engineers view themselves as invincible and therefore don't consider their departure occurring for many years into the future.