"Sole trader or SL?" guide (2026, in Spanish)
From Level 0 Mindset to Level 7: what each structure is, self-employed contributions by income band, the flat rate, what an SL costs to set up and run, income tax vs corporate tax, liability and when an SL pays off. Includes the hidden-costs pages (books, annual accounts, digital certificate, notary, VeriFactu) and a yearly table of a minimal sole trader vs a minimal SL.