Volunteer sign up plugin?

Anyone have suggestions for a plugin that would allow users to post what they need (for example, help with housecleaning, ride to doctor) and also allow users to sign up to fulfill those needs. I can find great plugins to manage volunteers, or to do a calendar, but having trouble (maybe it’s just finding the right search term) locating the exact needs my client has. An offsite example is SignUpGenius but client wants it on site.