The golden rule: decide how much you can actually spend before visiting a single vendor. In Spain, the average wedding runs €15,000–25,000 for 100–120 guests — but an intimate 60-guest ceremony might cost €8,000, and a large 200-guest reception can exceed €40,000.
Talk it through as a couple, then with family if they are contributing. Write the cap down. That is your constraint — everything else adapts.