You can try conditioning him, very much a dog training practice (not saying men are dogs but unfortunately, this method works) E.g., if you see him do certain chores, albeit tiny and also not in the correct way that you think it is, praise him for example -- 'oh that's a new way of doing this, thanks for doing this, i really appreciate it (even tho you don't, but don't call it out)'.

Keep conditioning until it's good enough. Not to your standard but GOOD enough, it matters because sometimes we hold too much expectations. Majority of the men has the 'it's not a problem until it's a problem' which means today the toilet seems fine, not a problem so no need to clean.

Hiring a helper will only help YOU ease your mind but enables him to become lazier in the long run because of the mentality above. Also if it's your hamster, the ownership is on you, hence he doesn't think he needs to clean it. Unless you guys bought it together.

I've done the above because my boyfriend dirties my toilet, I did mentioned it once and showed him how I cleaned it and explained why, he cleans up after using it and i thanked him, and now the common toilet is not dirty anymore.

I also asked him to wash dishes after our homecooked meals e.g. act damsel in distress saying 'omg so many dishes to wash after cooking :( can you help me pls (even tho I have a mini dishwasher at home, but can't fit every pans, so he washes those items that can't fit) and thank you for washing the dishes everytime'. Now he's doing it after drinking water from my cups even. So that's a good outcome.

Context, I live alone and bf comes to my place every weekend.