Both are standard office complexes- you are not allowed to wander in them quite, as both belong to the Bank. One, you learn, is used for handling bank business planetwide. The other is for handling bank business intergalactically- one of the main offices of the Banking Clan.
They are equipped with alarms and patrolled by casual night watchmen, who are assisted by a light patrol of battle droids. Way more droids patrol the bank.
Also, as an earlier note- you can fill in the blanks with the sewers as you explored them yourself. Not in excruciating detail, mind you, but well enough to find your way underneath the bank again.
Bear in mind the dangers of destroying battle droids before you're ready to make the heist. You only have one means of destroying them, after all- your lightsaber. Very tell-tale damage that it inflicts!
And again, that leaves your day open for more preparations. You haven't seen the inside of the bank yet and know nothing about it besides that they use battle droids, and you have no way to get off-world.
Good thinking! As you have no ship or the skill to fly one, it'd be grand to get a pilot.
You head downtown to one of the cantinas you saw on your way into the city. The cantina you choose- the Harping Dragon- is bustling with activity, with the regular assortment of aliens throughout. What is your entrance like and how do you intend to find a pilot?