Where the work happens

Two of the three requirements are about the storage rather than the work, which is unusual.

Three spaces

A bench for cleaning, trimming and preparation, which is wet, dusty and occasionally involves chemicals.

Storage for the collection, which needs a stable environment above all.

And somewhere for the backlog, which will exist whatever you intend.

The bench

Solid, because trimming involves hitting things.

Water and a sink, or a route to one.

Ventilation for anything chemical, and eye protection within reach rather than in a drawer.

Good light, and a dark background for examining specimens.

And somewhere to set a specimen down that is not the edge.

The storage

The requirement is stability more than any particular number. Around 45 to 50% relative humidity suits most material; a steady 55 beats a cycling 35 to 65.

Which in practice means an interior room. Not a garage, not an attic, not a basement that floods, not a conservatory.

Away from windows for the light, and away from radiators for the heat.

A cheap hygrometer, read occasionally, so you know what you actually have rather than what you assume.

And the cabinet itself matters chemically: raw wood emits acids that attack carbonate specimens.

What not to use

A garage, which is the default and the worst: daily temperature swings, seasonal humidity swings, and every failure mechanism in this property accelerated.

An attic, for the same reasons and worse.

A shed.

And a vehicle, even temporarily, which is where a show's purchases sit for a weekend and cook.

References