You know what looking through the notes I feel like I should reblog this with some of my anti-roach strategies, because contrary to a popular sentiment, getting rid of roaches DOESN'T have to be harder than dealing with the Whole Situation that would be either trying to get rid of an unwanted roommate, or entering into a formal roommate agreement with a stranger you know nothing about except "for some reason this person has resorted to living in my house without my knowledge or consent".
I once had a roommate who invited a roach infestation from hell. Multiple fumigations failed to get rid of them all. I took matters into my own hands. My apartment has been roach-free for years. Every now and then - maybe once or twice a year - one comes in from outside and I take swift action to make sure it dies quickly, as painlessly as possible, and without children that can reproduce. This shit works.
A fast-acting poison, to get rid of as many current adults as possible (or just. a shoe, if it's one freak arrival)
Insect growth regulator, to prevent eggs from maturing to reproduce
Do the usual thing with the fast-acting poison. Spray areas of high activity, try and find and spray any nests you find, spray around things that give off heat, keep it away from food and food prep areas and just keep those as clean as possible, everything that it says on the bottle or any reputable "how to get rid of bugs" guide.
Next, do a wide treatment of insect growth regulator. The main brand that sells it is Gentrol; it comes in foam spray and stick-up diffuser form. I find that the diffusers work best in general, but the spray makes a great extra boost. Does nothing to vertebrates, so you can use it pretty much anywhere...unless you have pet bugs or something, in which case you probably need to look up more specialized advice for pest bug infestations anyway, and...if you are a pet bug owner and you didn't think of that before then let me urge you to now because I would not want anything bad to happen to your pets because you wanted to get rid of the health hazard that is loose roaches.
If you see bugs shortly afterward with weirdly-shaped wings, that means the bad news is, step 1 didn't kill all the eggs, but the good news is, step 2 is working and these ones will not reproduce! The end is in sight!
Another thing that really helps is using Pine-Sol for regular cleaning. I find that most household pests HATE that shit, and it is just a really good general purpose cleaner. Of course, keep your space as clear of food trash as possible, but...this works even in an Oops! All ADHD! household. The extra step of IGR makes it a lot more forgiving than you may fear.
And there you have it! You'll be roach-free in no time!
This isn't to say that I think there's an objectively right answer to this; if you voted you'd rather have the guy because you're just that comfortable dealing with people in weird situations, even if they involve your home, I applaud you and we need more people like you in the world. Or, hell, I know in some particularly sparsely populated areas in some particularly inhospitable climates, "some guy got lost on a hike and so fucked up by the elements he had to live in my shed/cabin for a few days; well, that's why it's furnished and unlocked!" is just a thing that happens once in a blue moon and I think that's pretty cool.
But if your reasoning is that roaches are more daunting and hard to manage than the Surprise Roomate Situation and all the personal and potentially legal drama that will probably ensue...well, they don't have to be!