Ive just bought a p/washer lance gutter attachment etc.
To clean upvc gutters soffits etc, i would say it halves the time!!
I havent as yet cleaned inside gutters although have been asked, i always say.....
" i use a presure washer with attachments, it not only cleans them out but flushes all the guttering and checks the downpipes are clear by jetting them. yes it can cause the muck to come down the walls, but i clean that up for you.......But you are left safe in the knowledge, that they are totally clear AND sparkling inside!!!"
An old saying in sales "bullpoop baffles brains"
At the end of the day, they are paying to have their gutters emptied...thats what i will do.
If you fore warn them that it may cause a bit of a mess that you will clean up, then everyone is happy!!!!