Currency
Spain is part of the euro zone, meaning that Spain is one of 19 European countries who have adopted the euro as the sole legal tender. Neighboring countries Portugal, France, and Andorra are also part of the euro zone. Getting cash with foreign debit cards is easy from most ATMs, although you are best advised to do so before travelling to small towns. Banks and bureaux de change have change money, but have limited opening hours, are not open on Sundays, and may not be an option in smaller towns.
(Tripadvisor) (XE Exchange - beat bank rates by signing up to this)
Economy
The economic situation in Spain is still struggling with high indices of unemployment and public debt. Spain invested heavily in infrastructure in the late 1990s, but the financial crisis of 2008 hit the country's housing and construction sectors hard. Small businesses suffered and many people were made redundant. In the wake of the COVID-19, Spain is still struggling to get back on its feet.
Budget
Spain is cheaper to travel and live in than France and Italy, but slightly more expensive than Portugal. It is cheap by European standards to eat in a restaurant, and hotel prices are also quite reasonable in most places, except during special events in very touristic places. You can check hotel prices in (tripadvisor).
Other Budget Options - especially hotels. Look for hotels to search for different options according to your budget.
Museum (post - money - museum)
To know more about the history of Spanish economy, see the impressive vintage coin collection from La Casa de la Moneda