All Window Cleaners Trained, Vetted & Insured. Traditional Window Cleaners.Domestic, Commercial & Retail. Special Rates For OAP's, Single Parents, Unemployed
What does vetted mean 
I read their advert earlier and was sitting with the misses asking her the same thing. Could not come to a conclusion. Lol.
Punctuation in the advert is dismal to say the best. Something I personally think you should always get right when advertising in business.
Not meaning to sound to opinionated either.
With regards to the cost, Had leaflets like this going around here a while back. No where near as cheap as that. These where gardeners "Flawless" I think, advertising £6 per house, £8 for a 4 bed detached if I remember correctly.
Only them that will fail in the end.
Although the point about potential customers thinking we are ripping them off. I have found my best and least problematic customers are the ones I may have charged a good price for myself, and maybe on some overcharged. They like my service and have never had one problem. The ones that moaned to start are always a bit funny and the ones that moan about sinister things..