To rent a flat you have two options; one is to visit a property agent’s website and go through the listings, but this is not a recommended option for short stays because it will involve the broker’s fees. The second and a better way is to visit some kind of a virtual property board like Craigslist. Here you can find hundreds of flats and properties listed for rent for a day, week or month. The best thing is that there is no commission or broker fee involved. You pay to the owner of the flat straight away.
If you would really like to live in a hotel, then the best alternative is to rent a serviced apartment. It is considered a hotel cum flat because it includes a kitchen and is cleaned and managed by the management. You can find the listings of serviced apartments on Craigslist.
For your safety, do not send the money in advance to individuals displaying properties on Craigslist. Make a deal with them and pay them when you reach in London.
Before paying the rent, make sure all of the utilities e.g. bills and internet are included in the price.