Keep one Nice base for three nights
This four-day plan uses Nice for all three hotel nights. Visit Monaco as a day trip, then return to the same room. The final day has no new overnight allowance. Choose the room around the journeys you will actually make, including the airport or onward train.
Day one: arrive and settle into Nice
Drop your bags as arranged and take a short old-town or seafront walk. Leave a major paid visit for another day. A proper meal and an easy evening give you a better start than an excursion straight after arrival.
Day two: Monaco without moving bags
Take a suitable regional train to Monaco, allowing about 25 minutes station to station plus the journeys at each end. Choose the exit and local bus for Monaco-Ville, or start with Monte-Carlo and Larvotto.
Combine two nearby areas, lunch and one optional paid attraction. Check the return before staying late. Sleep in Nice again; do not add a Monaco room to this day.
Day three: give Nice a full day
Choose a museum, neighbourhood walk or beach time using the Nice guide. Keep the day flexible around weather and opening hours. An extra coastal excursion is possible if you prefer it, but requires its own ticket and return plan.
Day four: leave room for departure
Choose breakfast and a final walk close to your luggage and onward journey. If you want Cannes, add another night or make it the main activity on day three. Do not fit it before a tight flight simply because the towns are connected by rail.
Read the €386 example correctly
For one traveller, the day amounts are €114, €114, €114 and €44. They total €386: three chosen bed-night allowances at €70, four days of meals at €32, local travel at €7 a day and extras at €5 a day. These are spending choices, not available hostel offers or a surveyed average.
Add the actual Nice–Monaco return train, airport travel, other intercity journeys and paid admissions. If using a whole private room instead of one bed, replace the accommodation amount and divide only the room cost when sharing. Keep local buses within the existing allowance or adjust it; do not add the same ride twice. The city calculators are an alternative planning method, not an extra charge to add to this subtotal.
Price the Monaco day once
The checked ordinary TER fare is €6.10 each way, so a Nice return is €12.20 before a discount product. Keep that rail cost outside the €7 local-travel allowance already used in each day example. In Monaco, count a €1.50 app or contactless bus single, a €2 onboard ticket, or the suitable day product only once.
Use the route guide for the current source and save the return before leaving Nice. The same Nice room remains in the day-two amount; do not add a Monaco room.