When you use Keyword planner for research you find keywords with highest bid prizes and they are not long tail. It is a big problem to find them easily, related to business services with the minimum PPC cost.
Well there is the solution, you can use yahoo search engine to find long tail keywords and tell you what, they are exactly related to the type of services you offer with minimum pay per click cost. You can use these searches for your campaign. Go and search your keywords using yahoo search engine.