Hiring link builders
Link builders need a strange set of skills. They need to understand the internet and social networks and media, though they don’t really need to know much about SEO. Link builders tend to be the people who get stuff done, and can hustle a bit. It can help if they are popular online.
Training link builders
Don’t give them too much at once – give them a few things to look for at a time. Eventually, it will evolve into a progression where you can let them build links without your guidance. It can be time intensive at first, but it can be a good investment. In training, focus on specific cases and provide feedback.
Efficiency and cost control
One way to build this is to build up your brand name, so that people want to come and work for you. This can allow you to offer a lower salary, as they get other benefits. You can outsource developers and content writers, though be careful. Also, build internal tools that will save time.
Over time, you will develop an “SEO Black Book” of people you have linked to/who have link to you. Grow a list of relationships you form, not a list of links. Build partnerships and help people out, and that will come back to help you.