When I start any project I think keywords from the same service must have dedicated page. But as per client’s prospect they want quick result and their site has already indexed in Google with home page and also the home page have more anchor text based back-links with the targeted page. So it becomes hard to change the Google index page. AND as per statistic, service based dedicated page has better conversion rate than home page (I might not true)
So what you do in this condition. Also suggest some tactics to change the index page in Google fast.