For [EuroCG 17](http://csconferences.mah.se/eurocg2017/travel.html) conference, I will be travelling to Sweden and I am thinking of Airbnb. However, the trip is going to be paid by the [Special Account of National Funds](http://www.elke.uoa.gr/), thus I need a invoice (τιμολόγιο) to justify my stay.

Does a typical Airbnb stay (in general or Sweden, I think it will be the same) provide such a document, or should I explicitly ask the host for an invoice?