Here is a rough breakdown of some average costs for a 4-day vacation in London (excluding flights):
* Accommodation: The average cost of a double room in a mid-range hotel in central London is around £150 per night. If you're looking for something cheaper, you can find hostels and budget hotels starting from around £50 per night, or you could try renting an apartment or house through Airbnb or similar websites.
* Food: The cost of food in London can vary widely, but you can expect to pay around £20-30 for a main meal in a mid-range restaurant. You can save money by eating at street food stalls or markets, where you can find meals for around £10-15.
* Attractions: Many of London's most popular attractions, such as the British Museum and the National Gallery, are free to enter, but some, such as the Tower of London and Westminster Abbey, charge admission fees. The average cost of admission to a major attraction is around £20.
* Transport: The best way to get around London is on the Underground, which costs around £2.50 for a single journey. You can also buy a travel card that allows unlimited travel on the Underground and buses for a certain period of time. A one-day travel card costs £12.50.
On average, you should expect to spend around £1,000-1,500 for a 4-day vacation in London, excluding flights. This includes the cost of accommodation, food, attractions, and transport. Of course, you can spend more or less depending on your budget and preferences.