Operating out of many corners across Faerun in coverts operating independently from one another, Client's contact "Hands" whom intrust "Caretakers" with contracts complements their prowess. The means of acquisition are left to the imagination and independent freedom of the Caretaker entrusted. Leaving creativity in the eye of the beholder (So to speak). Or roll per the table below.

As a Caretaker you know every backstreet, backwater beggar and nefarious location to every major town or city. Certain establishments acting as Fishmonger's, Library's, Cartographer's, Tavern's & Alchemists operate as a "front" for distributing contracts and reports for "mark" locations. Presenting your dagger is symbol of your station recognising your place within the Blackhand Brotherhood. Presented to "Hand" or informants of "Black Network" Per the DM's discretion. For the right price these "fronts" will outfit you with the necessary poisons, equipment or information required to carry out a "mark", specific for your purposes. Provided you haven't discredited the Blackhand brotherhood and broken the fourth amendment. Otherwise you'll soon acquaint yourself with the "Fifth amendment".

Caretakers dedicating unwavering subservience and unflinching loyalty to the Caretakers is unparalleled. Hand chosen to be apart of an Elite sect of the Caretakers, personal cadre to the "Hand" as both security detail and spec ops force, tasked with the "Retiring" of outcasts (referred to as "liabilities"). Your secrecy and experience is the key to your success.  Your appearance is that of another caretaker that blends into the unsuspecting populous of present company within various locations acting as "fronts" to the operations of the "Blackhand Brotherhood". Underneath your garb, lie's a hardened veteran with years of experience invaluable to most circles. A unique spell called "Annulment" is bestowed appropriate for your station of prestige within the order.

Selecting the "Hand" background feature gives you an optional feature to direct and run your own "front" or have a personal "attache" withing your Dnd Campaign (Consult your DM). 

1). Perhaps you run a Fishmonger that carefully stuffs micro-parchment in tiny glass vials stuffed in assortments of fish transported in various marked containers over Faerun. Or a tavern transporting contracts stoppered in a bottle of booze, enchanted with minor illusion to make the bottles appear to be full. Maybe even transcribing hidden text in manuscripts in a Cartographer. Running your own establishment while generating an income with entrusting various interesting strangers approaching yourself at random intervals during the campaign may add an extra layer of immersion within your roleplaying game. 

2). Alternatively, perhaps your "front" was undone by the local law authorities, acting as a hand you have in your service three "surviving" members of the "Fifth amendment". One as your Right hand, carrying out your will & serve to protect you (whether NCP or PC characters). They may die or leave if frequently testing their loyalty as they come to terms that your no longer the controlling interest, and go on their own way in search of another "front" with another hand to serve.