On Game Options make sure Item Glimmer & Usable Object Highlight is turned On. This is an enormous help.
You have to destroy all 5 Bots in Minerva`s Den BEFORE you get on the Elevator! Otherwise you have to start all over again, because you cannot get back up again
Minerva’s Den 1/5
Head to the ‘’Rapture Central Computing’’ area (North). Open the first two doors and there should be a Gatherer’s Garden. Head to your left, the Vacuum Bot is right there, on the floor.
Minerva’s Den 2/5
When you find the Hack Tool, go to McClendon Robotics. Look for where the demonstration stage is. You should reach a big room with lots of water and with a bunch of enemies. The Vacuum Bot is moving around behind a barrier on the stage. Look for a big blue arch and a waterfall, the bot is directly behind the waterfall. I spent half an hour looking for this one and its the reason I decided to write this guide.
Minerva’s Den 3/5
Also in McClendon Robotics. Head to the ‘’Robotics Workshops’’ section. Go through the doors marked WorkShops, walk straight ahead past a COV machine, turn right into a room with consoles. Crouch down and at the back is a smashable vent grate. Go through into a room with a safe, audio diaries and Vacuum bot.
Minerva’s Den 4/5
When you enter the ‘’Air-Tite Archives’’ area, head to your right up a small staircase and you will see the ‘’New Accounts’’ marker. Head past a turret into a small room, the vacuum bot is right in front of you and (will also give Booze Hound Tonic)
Minerva’s Den 5/5
You need the ‘’Gravity Well’’ plasmid for this one.
Head to ‘’Rapture Central Computing’’ follow the ‘’Corporate Offices’’ indicators. You should see a closed door with an electromagnetic locker. Throw the ‘’Gravity Well’’ plasmid into the space above the door to unlock it. Turn to your right, open the door in the right corner and you will find what you’re looking for.
WARNING - FINAL REMINDER TO COLLECT ALL 5 OF THE ABOVE BEFORE MOVING ON AS YOU CAN'T GET BACK TO THAT AREA
At the very beginning there will be a battle. Afterwards take the door to your right (Programming area). Use your ‘’Electro Bolt’’ to access the door (to your left). The bot is inside this little room.
This bot is also in the ‘’Programming area’’. (It's near the Spitfire game)
When you get into the room with four visible consoles & fiery brutes take door to your right (past COV). Then pass through the second door, go up the stairs, take the door to your left, onto a small bridge and you'll see the bot on your right (near the machine gun upgrade).
When you pass through the underwater tunnel with ‘’Core Access’’ indicators, you'll see a Gatherer’s Garden to your left. Take the stairs that are to your left. Turn right and the bot should be on your left.
Directly behind the last one is a Little Sister vent and opposite this is an elevator. Take the elevator down. You need to come here anyway to collect Incinerate 2. When the elevator doors reopen the next vacuum bot will be right in front of you.
After melting the ice blocking Climate Control, go into the area. You will reach a room with a flashing red light showing Overdrive, and people frozen into place. Look for a Gene-Bank. Go At this point, go up the stairs where you will see a Little Sister vent and a door. Pass through the door head down the small stairs and the vacuum is in front of you.
I hope this guide helps, I spent so long and got so frustrated while searching for these I decided to write a guide to save others the hassle. I tried to be as accurate as possible please lcomment if you found an easier way to any of them. Happy Hunting!