Question
I'm running a marketing company and looking to work with contractors on SEO, Facebook Ads, and other social platform.
How and where do I find those contractors?
What results I can expect? How can I measure their performance?
Answer
Except Freelancer and upwork I have suggested you go with Linkedin. This is the best way to find contractors for your requirements.
In SEO, you can expect result after 3 months.
How can I measure performance? - you can check organic traffic for your top keyword rather then refferal traffic and direct traffic.
If increase the ranking of your targeted keywords and traffic then it's your pure result.