What exactly are you looking for and which area are you interested in?
They charge about 10% a month to manage.
You also pay for any repairs needed.
They typically charge about 1 month's rent to lease the property each time.
You sign an agreement with them outlining their legal obligations to you.
A good one, should want to treat your right so that you buy more properties or recommend friends and family to them to manage more properties. If you are unhappy you can switch.
They will charge a monthly fee and that's where you will need to negotiate with them