This company offered two lawn treatments, a spring fertilisation and weed treatment, for the price of one on a Groupon style website. Some six weeks following the weed treatment (which, I was assured contained a pre-emergent to prevent weed seedling sprouting), I counted 103 dandelions, patches of black medick, yarrow, great swathes of crabgrass and lawn spurge. I complained and following several unanswered phone calls and a no show appointment, he finally turned up. His view was that this was normal. Dandelion seeds, he informed me, have a three year life. No comments on why the pre-emergent didn't work, no comments on why the perennial weeds were still there. He did offer me a new 'deal': if I paid for two more treatments, he'd throw in a third one free! Not terribly impressed with their 'guarantee'.
I should have never had these [censored]s apply anything to my lawn. They killed my lawn, or should I say murdered it, it is now brown & crispy.