/biz/ - Business & Finance

Fellow españoles this thread is for us. I'm making it in English since I don't know if we can speak other languages in this board.
I've gotten to crypto fairly recently (about a year ago) and I've started investing taxable quantities this year. I've read stuff about crypto taxes in Spain on the internet but since I've never done it, I prefer you guys to give me your insight.
How do taxes work here? (I've read that they are different from IRPF, as in stocks)
Is it true that we have to declare crypto to crypto transactions and unrealized gains or just when we cash out?
Do they even have any way to know how much money we are dealing with?
Also how to evade taxes or any tricks you guys know will be welcomed.