At a premium
Definition 1 of 2
Pro Tip 1/3Scarcity and Value
Things scarce in availability but high in demand are often described as being at a premium. 
Post-pandemic, bicycles became hard to find, putting them at a premium.
Pro Tip 2/3Desirability
An item at a premium can be both difficult to acquire and highly desired by people. 
In the overcrowded city, an apartment with a view is at a premium.
Pro Tip 3/3Emotional Context
This phrase can carry an emotional weight, such as desperation or urgency, to secure something. 
During the blackout, flashlights were at a premium.