This is why so many choose Spain:
Obviously, the weather. Spain is very varied in climate and stuff. Generally, the Med' coast is much more expensive property wise, but a very short drive inland will see rents drop to 30% of coast prices. Winters on the coast are mild. Just a Two hour drive north takes you onto the high plain where nights are freezing with plenty of snow in the mountains. Be very careful when trying to choose a city to live in summer. You would not believe the difference in winter. Leon is a city I love, but from November to March it is chilly as fuck.
The average salary in Spain is below €12K. People live happily on this, although most would enjoy more. Tourism is big. Many earning the national average only work 8 months a year. If you have external income to the tune of €25K+ you can live very comfortably indeed.
More fashionable places cost more. Ibiza is a bitch for people like myself. The difference between rental prices and local salaries is disproportionate beyond belief. Many people work the season 10 hours a day, everyday for less than €5/hour - you have to if you want to save money. Avoid it even if you have €25K a year to burn.
One popular coastal example would be Malaga. Good climate. Good services. Beach. Mountains close by. International airport and easy flights back to the UK. Very affordable public transport. City bike scheme. Plenty of night life. Rent a room in a shared house from €150/month, a studio from €400/month, 1 bed piso from €500/month, etc etc etc. Short busride along the coast and you will have no trouble finding a Two, or Three bed detached house with sea views for €600/month. Fuel, electric, community tax, water etc... are all much cheaper and you use far less due to the good climate. Air con in summer is something I have always lived without comfortably. Gas/electric/water, about €25 a month for a single person in a studio.
WiFi and internet is everywhere.
The best thing about living in Spain for myself is the outdoor lifestyle and all that brings with it. I you are happy living in a small town you will quickly benefit from the relaxed, friendly and open attitude. There is no suspicion, or age barriers - everybody socialises together at all times. Large cities are a little more cliquey, and it will take time to find your niche.
The relaxed lifestyle has its downsides. Mañana syndrome is very frustrating and takes a lot of getting used to! In Spain if someone says tomorrow it may well mean next week - never take them literally. If someone says meet you at 8 in the plaza, don't be surprised if they expect you to be there waiting at 10, or later.
Plenty of places on the coast (especially Costa del Sol) where you can live 'English' and never need to learn the language. Some of the less fashionable resorts like Benalmadena are affordable, have some sort of naff charm and great facilities, services etc all run by English speakers. Around 50% of the population here is non-Spanish. Love the places to visit, but it isn't the Spain I choose to live.
If you enjoy sport you will love Spain. Every city has fabulous sports facilities including outdoor pools for summer. Not uncommon to find yourself playing tennis after midnight in the summer on fabulous floodlit courts for example.
If you are considering buying property, leave it a year. Brexit has caused big wobbles for UK based buyers. Many want out now. Prices in areas with lots of UK expats and little in the way of local economy are in freefall. If you fancy isolated living in the mountains of Andalucia working from your laptop, a Two bed restored farmhouse could be yours for less than €30K.
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Cigs €5/packet of 20. Tobacco €5 for 30 Gramme pouch.
MJ and hash readily available from €3/Gramme for good.
Many meds from the chemist available without prescription. My salbutamol inhaler just cost me €2.69 over the counter. Good quality pain killers etc - very cheap, no prescription.
Booze dirt cheap. Most supermarkets will stock small 33cl cans of beer from a little over 20 Cents each. Branded Scotch, or Vodka from a Tenner a 75cl bottle. Cheaper stuff available. Drinking in bars: most major cities you can find bars offering a tubo for a Euro most times of day. Quality wines very affordable. Good Crianza just €2.50 a glass in most bars.