We have been lucky and have not had to do much paid advertising in our history. However, we added nicejob to jobber 2 years ago. We have solicited almost 800 reviews. I have ensured the requests for a review are written in a way that if a client is unhappy, they will let us know first so we can rectify the issue (which we almost always do, even when it unreasonable and hurts to do). This is valuable in getting some repeat business but mostly to ensure that if a review is left, it is positive and usually outlines the outcome of the complaint. We now have a 4.9 star rating on Google which has kept our requests queue full.