Should be tipped every time really, I have my car cleaned every week 12.00 always give 15.00, and the guy that delivers my Indian always gets a tip, aswell as the lady that cuts my hair monthly gets a tip, surly window cleaners should fall in same category , I remember the good old days of tips. Now we only undertake commercial we have to treat them, spent 500.00 at the wine merchants this year
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