Numbeo is accurate for the cities I tried, but in many areas there are very cheap long term basic accommodation and only luxury travel accommodation for tourists.
I think that someone who asks this question has a finite budget, the option to go where he wants and desires to get the most "bangs for his bucks". Most of the answers I saw were for luxury business trip to a fixed location.
Also cost of traveling is relative to the way you travel, what you do, and for how long. I think it is best to separate things into various expense items.
Yes, the money for the plane ticket may already be spent, but the length of the trip gives you a daily budget. A $1000 ticket for a 2 weeks trip is not accounted the same way as a ticket for a 2 month trip. This impacts your total spending and has to be integrated into the trip as a daily expense. This can lead to going to a more expensive country that has a cheaper travel cost.
There are some good sites for hotels but many of the hotels listed pay to be there and are desperate for customers because they are badly located and not- competitively priced. The main problem however is that they only tend to list hotels with 2-3 stars and above. In Europe that is fine but in most countries I travel to, budget hotels don’t want to pass the burden and expense of being rated by stars giving agencies. So, the bottom range in hotel sites are middle range in many countries and many under $50 hotels with great values just do not exist on the internet.
This cost greatly varies; sites like Numbeo are good for that. Meal budgeting is very personal and is one of the great variation. To save money there are usually many cheap street foods and supermarkets.
Either cost of inner-city transport or averaged daily inter-city transport.
One of the greatest relatives, from near zero to spending most of the budget in discos and pub crawling.
- Miscellaneous, Groceries, Fees
Variable, in some countries miscellaneous costs can be greater than hotel and food. Museum and sites fees can be a separate category if they are major daily expenses.
So, to answer the question you need to do some estimates based on several sites on the different components of the budget.
So these vary, while some people put over 60% of their budgets in hotel, for me I like cheap hotels but nice food, and a social life. So for me I would estimate based on 100 that travel=10, hotel=30, Food=25, transport=5, Social=20, Misc=10.
So, determine your budget priorities and get estimates on these areas.