Tourist Tax

Here in Catalunya for every guest over the age of 16 hosts have to pay €0,90 per person per night, up to a maximum of 7 nights. This applies to Hotels, hostels and and holiday guest accommodation.

This means that if I have a full house for a week it costs me €0.90 × 6 x 7 = €37.80 for the week. At present I am covering this / including it in the price of the accommodation.

For more details

https://www.spain-holiday.com/rentalbuzz/catalonia-tourist-tax-explained