Electrician
There are a few electrician disguises in the basement of the terminus hotel. The one nearest the elevator can be distracted by sabotaging the circuit breaker and then subduing him.
Janitor
Enter the Terminus hotel, take a left and enter the bathroom. Crawl through the vent and come out in the laundry room. Go out the back right door. A janitor will patrol this area so wait for him to appear, subdue him and take his disguise.
Hope Goon
There is a long coat room on the 8th floor not far from the large bear. You should find an unused disguise in this room on a table.
