Hosts might ask you to pay for some costs like cleaning fee. This must be written in their profile under "additional information".
Additionally, in some countries, you might need to pay tourist tax but you can check that with your host or local authorities.
In the event that there are no pre-established rules, both parties must reach an agreement on these details during their conversations.
You are free to organize and arrange everything with your guest or host.
We strongly advise you to discuss these details BEFORE finalizing the exchange to avoid bad surprises later.