What level do i have to be to get Daedric items from the Dremora merchant?

In the Dragonborn DLC you get a power called Black Market which allows you to summon a Dremora merchant to trade with. You are supposed to be able to frequently buy Daedric items from him when you reach a certain level but I don't know what level that is. I am a level 36 dark elf and can only buy ebony from him. When can I buy Daedric?

The Dremora merchant's inventory is levelled. He's a reliable source of Daedric gear, but that doesn't mean he gets it earlier than it would otherwise start showing up.

Daedric Armor is the best heavy armor in the game. It appears in leveled lists starting at level 48 (enchanted varieties at level 49). However, even after level 48, Daedric armor is twenty times less likely to appear than other armor types.

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Daedric Weapons are the best standard weapons available in the original release of the game. The Dawnguard plug-in introduces Dragonbone weapons, which exceed Daedric in quality. They appear in leveled lists starting at level 46 (enchanted varieties at level 47).

The Dremora merchants weapon stocks are levelled¹. You would therefore expect Daedric items to start appearing regularly at level 48 for armour² and level 46 for weapons³. Enchanted weapons and armour begin to appear one level after the base level mentioned above.

It is suggested in the first linked source that they can in some cases appear uncommonly up to twelve levels before these thresholds.