Several of my friends have cleaners, don't worry about it. They are not minted, or snobs, they are just busy people with social lives, and they figure that £20 a week, the price of a night in the pub, is worth it to have a nice flat with no hassles.
I would say that word of mouth is the best way of getting someone trustworthy. Also, a friend of mine worked through an agency and was royally ripped off. If you go direct to someone, at least you know that the woman doint the work gets the money.
Meggles, where do you live? I might know someone.
Vicky