Martin's Contraband is Martin's shop located in the Hanged Man in Dragon Age II. It becomes available after completing Finders Keepers during Act 1, if you help Martin.
Act 1[]
Name Price 
Deathroot Toxin (x2)
73 
4
Crow Venom
36 52
Debilitating Poison
36 52
Combustion Grenade (x2)
36 52
Note: He sells two random generic pieces of armor and two random generic weapons.
Act 2[]
Name Price Deathroot Toxin (x2)
73 4
Debilitating Poison (x2)
36 52
Crow Venom (x3)
36 52
Tar Bomb (x2)
54 28
Combustion Grenade (x2)
36 52
Note: He sells two random generic pieces of armor and two random generic weapons.
Act 3[]
Name Price Fell Poison
1 36 95
Deathroot Toxin
73 4
Debilitating Poison (x2)
36 52
Crow Venom (x2)
36 52
Mythal's Favor
73 4
Tar Bomb (x2)
54 28
Combustion Grenade (x3)
36 52
Note: He sells two random generic pieces of armor and two random generic weapons.
Day/Night[]
There are actually two versions of Martin's shop, one for day and one for night. This can be exploited to buy two of Mythal's Favor for less than the price of crafting one. It can also be used to obtain Combustion Grenades for slightly cheaper than their crafting price (up to 6).