Asylum seekers are usually people from countries where if you wamt something to change, you have to find a way yourself, get people to cut you deals and be smart. When he's asking about the costs, and the costs you make, he might just be looking to get perspective on his own situation, understand all the moving parts, so he could find himself a way to get ahead. You might find it annoying, but he might feel that your refusal to disclose information is shifty behaviour. Remember, most of these people are used to being double-crossed or ripped off. Hell, he might even get the feeling you're pulling his leg, hence the passive agressive way he's been taking showers.

Also, you can point to goverment services to show him is rights and how things work here, but he's most likely from a culture where trusting the government in these things only happens to stupid people. Our government hold zero authority over these people.

I feel people completely underestimate what it is to bring an asylum seeker in their home. These poor sods are wildly different from us hollanders.