PhD in Management from US

1 - The recommended minimum is 700. If you can get 720-740, that's great.
2 - Everything can affect your chances, given how competitive the process is, but this shouldn't be too much of a problem. GPA is not considered one of the main factors for PhD applications, unless you're really bad at it.
3 - This is something nobody can really answer for you. It's very specific for each applicant, as different applicants look for different things, have different criteria, with different weights. A good list of schools will be a good fit for the strength of your profile (something we don't know), for your specific topics of interests (we don't know yours, and rarely someone will know the topics of interests of all major schools in management), for the kind of experience you are looking for during the PhD (culture and values can be very different from school to school, the city you're going to live can also be an important factor to take into consideration), and for your goals in general.