I would suggest utilizing Upwork.com for finding an expert. This site will allow you to create a detailed project proposal based on your needs and give you maximum flexibility to create a payment structure that fits your budget. Depending on how the training is structured, you can pay the expert you choose either by the hour or session. Holding online training seminars with multiple individuals would be the most economical and effective way to accomplish your goals, then if needed, you can find another expert with at a lower rate to help answer further questions the attendees might have at on later date. This task could be performed at an hourly rate, as the bloggers would most likely need about 30 minutes of time to reinforce concepts learned during the seminar