Calculate "owner earnings" to get a true reflection of value.
Focus on return on equity, not earnings per share.
Earnings can be pliable as putty when a charlatan heads the company reporting them.
Asset values and earning power are the dominant factors affecting the valuation of a controlling interest in a business. Market price, which governs valuation of minority interest positions, is of little or no importance in valuing a controlling interest.
The dominant factors affecting control valuations are earning power (past and prospective) and asset values.
If you don’t feel comfortable making a rough estimate of the asset’s future earnings, just forget it and move on. No one has the ability to evaluate every investment possibility. But omniscience isn’t necessary; you only need to understand the actions you undertake.