A relative kept wine for thirty years and now the bottles are yours. Some look serious, some look forgotten, and none of them came with a list. Before deciding what any of it is worth, you need to know what is there and what condition it appears to be in.
Record the shelves before you disturb them
Photograph each shelf, rack and box in place, then count. The arrangement itself is information: bottles kept together were often bought together, and the ones at the back of a cool corner have usually had a better life than the ones near a radiator or a window.
Old bottles carry sediment. Moving them stirs it up, and standing a bottle upright dries a cork that has been wet for decades. Do the recording first, move gently, and let anything you do move rest for a week or more before opening it.
Read the fill level and the closure
Fill level, also called ullage, is the gap between the wine and the cork. Producers fill to within about three to ten millimeters at bottling, and wine is lost slowly afterwards through the cork and by evaporation, which is why auction buyers treat fill level as a condition signal, as Decanter explains. It is the best clue you have when nobody can tell you how the bottles were stored.
A cork pushed above the lip, or dried wine on the neck under the capsule, suggests the bottle was warm at some point. None of this is a verdict on how the wine tastes. It is a way to decide which bottle to open first.
Producer, wine and vintage: Quantity and bottle size: Fill level: neck / top shoulder / mid shoulder / low: Cork pushed or seepage: yes / no: Capsule and label condition: Where it was stored, if known: Priority: open soon / keep / get advice:
Open the uncertain bottles first
Bottles with lower fill, damaged labels or unknown storage are the ones whose condition you cannot predict, so they are the ones worth opening while you can still learn something. Open them without ceremony, over an ordinary dinner, and write one line about what you found.
Those lines accumulate into a picture of the whole collection. If three bottles from the same shelf are tired, the rest of that shelf probably is too, and you can stop treating it as a reserve for later.
Get advice before selling anything
Selling wine privately is regulated in many places and licensed in others. Auction houses and merchants assess provenance and condition before they quote, and both are questions about storage rather than labels. Ask before shipping bottles anywhere, because a warm van undoes the evidence you are trying to present.
If a bottle looks valuable, resist the urge to look up a price and write it into the record as fact. Note what you observed and where the estimate came from, and keep it separate from anything you paid.
Give the collection a location system
Once the triage is done, the collection needs the same treatment as any other: stable names for each rack, row or box, and a record of what is in them. The rack and row guide covers a naming system that survives a rearrangement, and the inventory guide covers the first full count.
Record what you drink as you drink it. An inherited collection often shrinks faster than it grows, and the history of what was there is worth keeping even after the bottle is gone.