Summer stay in London

I am from New York and will be in London for an extended period for business (I work in finance) between mid May and late August, and am looking for a place to stay during this time. I'm generally quite flexible and easy going and won't be in the flat much.

Have a strong preference for a full flat (studio or 1 bed) in west and central London but can be flexible for the right share. Ideally in a nicer or more modern building (with washer in unit), but does not necessarily need to be a luxury building. Budget is somewhat flexible depending on the situation.

Do not smoke nor have pets.

Thank you.