I'm in Catalonia, Spain (for a few more weeks) and do not recommend. I don't know what you are making, but I am also an Autonomo, and I'm being royally fucked on social insurance and taxes. My tax and SI bill for this year will be around 60%, and fuck that. And yes, I have tried different accountants. Essentially, the tax department decided that a lot of my expenses are not allowable, and because I have bank accounts in other EU countries as well as Spain, they decided that I am "probably hiding something" (their words). I can go and spend a lot of money on lawyers, or I can just pack up and leave.

Combined with the bullshit Catalan independence movement and accompanying social and economic instability, generally unfriendly Catalans, terrible quality of food (essentially salt, with a hint of whatever it claims to be on the package), and the "we will bill you whatever the fuck we want, good luck clawing your money back" utilities (literally opened a 400 EUR bill from the phone company 10 minutes ago), I am totally done with this place.

I have lived in many countries, and all places have challenges and ups and downs. This place, however, is the pits.

Spain does the same thing as Portugal, for company workers, where they "hide" part of the social security payment from payment receipts. Companies pay 23.6% and the worker 4.7%. Only the latter appears in the salary receipt, the other is a company expense.

Edit - it's 29.3% of the base mínima de autónomos - which is about 920 euros a month. Now, I honestly have no idea what that actually means, but it means you pay about 270 euros regardless of what you earn (it's a stupid system that benefits the well-off).