Quick answer: Medellín runs about EUR 45 per day mid-range - noticeably less if you eat local and walk. Cheapest window: December–March (drier); spring-like all year.
What things actually cost
tinto (small black coffee)
0.50 EUR
menu del dia lunch
3.50 EUR
metro or Metrocable ride
0.70 EUR
craft beer
2.00 EUR
Uber 15 minutes
2.50 EUR
fresh fruit juice
1.20 EUR
Eat well for little
Bandeja paisa - the mountain of beans, rice, chicharron, egg and arepa, 5-7 EUR at a traditional spot like Hacienda
Menu del dia at any corner restaurant - soup, main, fresh juice for 3-4 EUR, the everyday local lunch
Arepas de choclo from street carts - sweet corn arepas with cheese for about 1 EUR
Pergamino on Via Primavera - the benchmark Medellin specialty coffee, pour-over around 2 EUR
Mercado del Rio food hall - dozens of stalls from ceviche to burgers, mains 5-9 EUR
Money mistakes to avoid
Dar papaya - flashing your phone on the street or in taxis; keep it pocketed and stay aware, especially downtown and at night
Never leaving the El Poblado bubble - Laureles, Envigado and the Metrocable lines show the city people actually live in
Hailing cabs on the street at night - order through Uber, InDrive or Cabify instead
Planning outdoor days without a rain buffer - afternoon downpours are routine, so do viewpoints and Guatape in the morning
Transport without the tourist tax
The Jose Maria Cordova airport sits 45-60 minutes outside the city; shared shuttle vans cost about 4-5 EUR and a taxi 20-22 EUR. In town the clean, safe Metro plus Metrocable costs about 0.70 EUR a ride, and Ubers rarely exceed 3 EUR.