Quick answer: The best time to visit Lima is December–April (summer, less grey). Expect a mid-range budget of about €55 per day. Visa: Visa-free for most EU/US/UK passports (up to 90 days).
Why this window
Lima is a food city with ocean cliffs. Three days: Miraflores coast, Barranco's street art and the historic center — plus the best ceviche of your life.