A Facebook Ad

I'm looking to create a Facebook ad to generate leads for a fitness gym center. My target audience for this ad is young adults aged 18-45. My budget for this ad campaign is under $500. I'm looking for creative and effective solutions that will help my agency reach our client's goal! Another thing, most importantly I am looking for a minimum of (3 month contract) with my freelancer.
Please include examples of your previous work with Facebook ads in your proposal. Also, I'll send you details of the ad after you get the contract...
I HOPE YOU WILL BE THE ONE. Thank you!