Taking the first two paragraphs, all the highlighted sections need revising:
The ability to find a house, is [Why have you put a comma after "house"?] becoming very difficult for many people, especially in the main cities, and London is one of them. The prices for houses to buy or even to rent are increasing during the last ten years.[Verb tense- you are talking about something that has been happening in the past
I was looking the other day for a house to rent, in [Why a comma?} central London to be closer to where I work. I have to say that I had the most stressful time ever in my life. I couldnít find any property where I hoped for. One of the reason is ["One of" implies a plural but you have a singular noun] that my budget wasnít enough, [Why a comma?]I had to wait nearly 2 months to find the right place. Luckily I did a research in the ["do research" "on"] internet, and spoke to the estate agency[Did you only speak to one estate agents, or more than one?], they were very helpful. We arranged for a day to look at the flat, and that [what does "that" refer to? - If it is the flat, then "it"]is exactly what I wanted, but I didnít know that things can get worse and complicated, singing the contract and processing the payment ,it is so hard.
"Hyde Park" does not require an article.
"Oxford Street" requires capitalization.
You have a flat - it is not a house. You can say "My home" or "My flat"
You do not generally have two "master bedrooms".
I am not sure that the passage can be regarded as being "about houses" - it is about you finding a flat. Is this what was wanted?
Student or Learner