Margen
Look at your home policy and find two numbers: buildings and contents. The first is what it would cost to put the building up again; the second, everything inside it. Almost nobody has looked at them since the day they signed, and that is where the trap is.
Article 30 of Spain's Insurance Contract Act calls it the proportional rule: if you insure for less than the real value, the company pays out in that same proportion. You declared €20,000 of contents and you actually own €40,000 in furniture, clothes and electronics: you are covered at 50%. Burglars get in and take €10,000 worth of things. The insurer transfers you €5,000. They are not cheating you: they are applying the law and your own policy.
The trap works the other way round too. If you declare €60,000 and you only own €40,000, you have spent years paying premium on €20,000 you will never collect, because no insurance pays out above the real loss.
Twenty minutes tomorrow: walk the house room by room and add it up at replacement price, not second-hand resale price. Compare that number with the contents figure on your policy. If it does not match, ask your company in writing for a clause waiving the proportional rule. Plenty of them include it without touching the premium, but only for the people who ask.