Prices in Spain vary by region, and within each region.
According to the data collected by Holidu.es, a vacation rental in the country costs around 180 euros per night. However, if the prices are analyzed in detail, these vary considerably depending on the region. In Spain, the most expensive destinations are spread from north to south, as well as including the popular islands and coastal areas: the Balearic Islands are in the lead with an average price of 331 euros, followed by the Basque Country which reaches 300 euros and in third place Catalonia with a price of 207 euros.
I'm guessing I need to reconsider my rates for next year - currently most people pay an average of €105 a night, which is the same if there are 2 or 6 people, although if people ask I often reduce this for one room use.