You need to understand that the chances of you coming to the uk are slim to none. We hear of these scammers conning unsuspecting people many times. DO NOT SEND MONEY.
IF you look on Google maps, the addres you give shows local authority housing and blocks of flats. I don't think these people will have the money to bring a Nanny or AuPair. They are probably Nigerian scammers.
If it sounds too good to be true...... it probably is
