“Toiletries” are usually used to describe personal hygiene items — for example, shampoo, body wash, lotions. That’s why you’ve seemed to have confused a bunch of us, because hosts aren’t responsible for those.
As other folks have mentioned, it’s not OK for a host to leave a dirty house and there are other potential ways to address that, rather than by automatically taking the reimbursement route.
Of course, you can ask the host where their cleaning products are, and if during your discussion it turns out there aren’t any, ask whether they want you to buy some and be reimbursed.
Frankly, to me, if they have no cleaning supplies and have left a dirty house, I’m not cleaning their home (and it’s unlikely I’d stay if it’s filthy, meaning really dirty). Why: I do THS as an equal exchange and I’m not providing a cleaning service for pigs with no regard for sitters. I haven’t encountered such, but if I did unexpectedly end up in a pig sty, I’d give them 24 hours to find alternative care and report the filthy home to THS. And if our sit ended up technically sticking on THS, so I could write a review, I’d give them the lowest rating possible and make explicit how filthy their home is, with factual examples, no emotions.
If more sitters did so, more filthy hosts would be driven off THS. I say that, because THS doesn’t lean toward ejecting hosts even in such cases, so sitters should exercise their power to protect ourselves and other sitters.
BTW, it sounds like you’re also possibly trying to earn a living. THS isn’t a platform for that. If you need to do that, you can find work otherwise or maybe switch to another platform and do paid sitting, which is in violation of THS terms.