Old baseball cards value is harder to read than modern value for two reasons: there are fewer sales to read, and the surviving cards vary enormously in condition. Both problems have the same solution, which is to be stricter about which sales you count rather than to gather more of them.
Fewer sales means a wider window
A card that comes up three times a year cannot give you five sales from last month. Widen the time window rather than loosening the card: three sales of the right card over a year is better evidence than five sales of something similar this week. Report the result as a range and expect a patient sale.
Wider condition range means a tighter filter
Pre-1980 survivors run from pristine to badly damaged, and the price difference across that range can be a multiple rather than a percentage. Choose comparables that genuinely look like your card, and if the only sales you can find are of much sharper examples, adjust your expectation downwards rather than using their price.
Graded sales are often the clearest evidence
For older cards a high proportion of the meaningful sales are graded, because that is where the serious buyers are. Those sales are easier to read because the condition is stated. If yours is raw, graded sales at a low grade are usually closer evidence than graded sales at a high one.
Then do the arithmetic and keep the spread
Put what you found into the card value checker even when it is fewer than five figures: the high, the low and the spread are as informative as the average when the sample is small. A wide spread on an old card usually reflects condition rather than an unstable market.
Questions people ask about old baseball cards value
How old is old?
For this purpose, before about 1980, when print runs were smaller and storage was rarer. Earlier is generally scarcer.
Are damaged old cards worth anything?
For genuinely scarce early cards, often yes, at a heavy discount. For common ones, usually not.
Should I have an old card graded before selling?
Only if the arithmetic supports it. Scarce and sharp is the combination where it usually does; run the cost and uplift calculators.
Why do I see such different prices for the same old card?
Condition, almost always. At that age the condition range among survivors is very wide and the price range follows it.