Cathedral of St. Vincent: 

(you will need to search every place in this mission to satisfy the loot requirement, do not pass up on any place to find loot)

wait until second guard approaches your cell then take his Lockup Key, use it to open cell door, go right, wait for guard to exit guard booth again then enter, take Locker Key off the wall then get coins inside guard booth to get loot objective,

exit guard booth and open door to ramp walkway to get to upper level, go behind guard desk and open small locker drawer with the Locker Key to escape cell and get blackjack back and to get new objectives,

knock out guards here then read the incident report on the desk to get new objective,

open front doors and exit the City Watch Station, go through archway and knock out patrolling guard, wait for guard in black to come out of library door here, knock him out and take his Code Vault Key Six, go down street to left of library doors and go through archway, go to ladder leading up to window with a note on the ground, go past this ladder to next archway, wait for female guard to come by, knock her out and take her Code Vault Key Five, go through next archway on the left, turn right beside stone ramp walkway, stay right down alley until you find dead man in the corner, take his Morgue Key, from dead man go straight then stay left, watch for male guard in black to come by, knock him out and take his Code Vault Key One, also back here in an alley is a metal helmeted guard in blue patrolling, take his Sewer Hatch Key, go back to where dead man was lying in the corner and go through archway to the right after leaving his body, go past water fountain through next archway, open door up some steps to enter mayor's house, go down long wooden hallway, turn left and get Basement Key hanging on the wall, use this key to open wooden door on the right here to get down to the basement, read scroll in the basement to get new objective,

go back upstairs to exit the basement, sneak into open room where two guards and a man are talking, slowly enter and hide in this room to pay mayor a visit to find out more,

wait for this conversation to end to find out who framed you and to get new objective,

if this objective does not complete then you will need to read the mayor’s book up in his room, after conversation knock out female guard and take her Code Vault Key Three, in this same room where the conversation was flip the wall lever under the painting of a girl dressed in white to move the painting, take the Conspiracy Evidence, go upstairs and knock out guard next to gambling table and take his Code Vault Key Two, knock out mayor in his room and take his Water Utility Management Key, on his window sill read the book, this might be necessary to find out who framed you, go back downstairs and exit through door near open room where conversation was to get out by the canal, knock out patrolling female guard out here and take her Code Vault Key Four, go along canal to find Water and Sewer Management building, open door with Water Utility Management Key, open sewer hatch inside with the Sewer Hatch Key, go down ladder to sewer water, knock out patrolling guard down here and take his Code Vault Key Seven, go left and open metal door at the end, enter room and get the Code Vault Key Eight to relieve the eight thieves of their keys and get new objective,

get lockpicks in this room and the Birdcall, also get the Black Bones Ledger Evidence off table in this room, go back into sewer water and go left to reach a long tunnel with another ladder at the end, go up ladder and open hatch to get into the cathedral storage room, enter hallway with open room where small holy water pool is, knock out patrolling Hammerite guards, wait for Hammerite priest to come by, knock him out and take his Priest Michael’s Room Key, go to the bottom floor of the main cathedral room and look up to see some wooden platforms, you need to get to the first wooden platform, find square plate on this bottom floor in the corner that says NE Hall of Silence, go up ramp walkway next to this square plate, do not go all the way to the top floor up the ramp walkways yet, go down the first set of stairs you reach on the right after going up the first ramp walkway from the floor plate, go down hallway and past Priest Bartlett’s room, you will need to search around each room for some rope arrows in a chest, open double doors at the end of the hallway to enter large wood floor room with fireplace, open first double doors on the left to enter stone hallway, go to small open window, go left of this window and up ramp walkways to narrow hallway, go straight then left to reach the first wooden platform, shoot rope arrow up to wooden platform above this one, climb up and shoot another rope arrow to the highest wooden platform, get the Magic Hammer at the top, enter crawl space up here and climb down ladder inside to get back down to the first wooden platform, now go back down to the lower level of the main cathedral, go back to the first hallway where you entered after the storage room, go into the small open room with the small holy pool of water, drop the Magic Hammer into the holy water to get Blessed Hammer, go back to the plate on the ground in the corner of this bottom level that says NE Hall of Silence, go back up the ramp walkway and this time continue going up each ramp walkway until you reach the very top level, stay to the left, take the first left towards a large hammer statue, enter hallway and open Priest Michael’s room on the right with the Priest Michael’s Room Key, flip lever inside this room on the right side of the desk to move painting and reveal padlocks, you must unlock the locks with the code vault keys in this order: 1 – 2 – 3 – 4 on the top and 8 – 7 – 6 – 5 on the bottom, read the Code for Hammerite Vault to obtain codes from code vault and get new objective,

you now have code 0457 for the first door and code 6189 for the second door, read the Instructions From Gutsy in your inventory to find out more about the Black Bones Thieves Guild robbery,

exit this room and go back left, turn right in next hallway then left to reach vault door one with keypad to the right of it, enter code 0457 to open this door, use Birdcall to change the light on the keypad to green to disable the alarm, now enter code 6189 on the keypad to open the second gate door, use the Blessed Hammer on the large hammer statue, take the Sacred Hammer of St. Vincent to steal hammer and get new objective,

go back down ramp walkway, go back to the stairs and back down the hallway and back past Priest Bartlett’s room to get back to the large wood floor room with fireplace, open doors to left of the fireplace and go up narrow stone ramp walkways to reach Lander’s office, go left to library area, go to the Seamus Archive section, you will see a plate on the ground that says Seamus Archive, get the red History of St. Vincent Hammer book beside standing person in this section, read it to get history book,

you are most likely still short on loot so find guard booth with large unfrobbable ground lever inside, get the Bell Tower Key hanging on the wall, go down narrow stone passage near this room to reach locked single door, use this key to open the door, climb the ladders inside the tower, in the section of the tower before reaching the top look at the wooden railings to see a gold nugget stuck in the corner of the railings, go back to bottom level and back into storage room where you first entered, go back down the ladder you came up with to get back down to the sewer water, go back to the first ladder and go back up to the Water Utility Management building, exit the canal and go back to the City Watch Station where you started this mission, go back down to the cell level and open the orange door with the Morgue Key, enter Morgue and get the Evidence Bottle off the table with the dead man to get new objective,

exit the Morgue and enter the canal, search through the water in the middle area to find Gutsy’s Watch, use the Evidence Bottle on the watch to collect it, go back to the Morgue, flip lever on the machine then drop the Evidence Bottle with Watch collected in it inside the machine, flip lever again and take the Auto Lift Print Evidence to find evidence to prove and clear yourself and to get new objective,

now drop all four items onto the table next to the machine, drop the Conspiracy Evidence, Evidence Bottle, Auto Lift Print, and Black Bones Ledger all onto the table to bring your evidence to the examiner’s table in the morgue,

exit the Morgue and exit the City Watch Station, go right and enter the Morris Tunnel to end mission