Website for advertising discount gym memberships

Need website for advertising discount or used gym memberships. Allow users to post online. No payments to be made. Just a free website. Mobile friendly. If an app needs to be made then I dont want to Need website for advertising discount or used gym memberships. Allow users to post online. No payments to be made. Just a free website. Mobile friendly. If an app needs to be made then I dont want to have to remake the website with it. Needs a messaging service. Email notification and message in website. User portal for people...