Things to remember :
1. Visa on arrival is time consuming if there are many flights arriving at the same time, careful while planning.
2. Taxi is the most expensive thing you'll end up paying to, often more than what you expect.
3. Do try to use public transport wherever possible. Avoid taxis if not in a group.
4. Use klook to book activities, sim card, metro pass and other stuff at a great discount.
5. Always prefer to walk, You make memories, explore the city and save a huge amount of bucks.