Public Health Inspector here- this is a good link that I give people. https://myhealth.alberta.ca/alberta/pages/pests-cockroaches.aspx
Is it definitely the landlord that has to pay for pest control?
Typically yes it is.
Also, I have seen 1 big one and 3 little ones. I've managed to kill them all. I can't see anymore today. Do you think I should still get pest control or glue pads?
Hi! I'm a property manager! Do you live in an apartment complex? Tell the landlord and have them send pest control. You need to prep your apartment ahead of time though. Just look up how to prep for roach treatment on google. It may take several sprays and they can only be done every two weeks due to the roach life cycle.