How Much Do I Charge This Potential Customer for Social Media Posting? I Need Help!

I have potential client that is interested in 4 - 5 posting for social media sites daily. I will have to post to 4 - 5 different social media websites. So, in other words each of these social media sites will being updated 4 -5 times per day. One of the social media sites will be Twitter.

This client will provide me the tools necessary to complete the gig. He is looking for someone to work on his project long term, at least for one year. He has tried outsourcing for this job, but he has not been able to find consistency and the language skills of the Indians and other foreigners he hired lacked.

What I have to figure out is how much to charge him for a trial period of 30 days. I am totally clueless as to how much these services cost. I really want this job because this guy has a lot of knowledge to offer and teach me, so I am really eager to get this client.

If you have a clue and knowledge about this sort of thing, please chime in and let me know what I should charge for these services. I have to get back to him in about 4 hours with a price, a deposit amount, and some terms.

So, how much money should I charge?