There are severals ways to accomplice git to FTP. One way is using a 3rd party SaaS which usually hosts your repositiories too. Another way is to use a local deployment like GitFTP-Deploy where everything happens on your computer. Depending on your team size you should choose a service that fits your needs.
This is comparing apples to oranges, but way give you a idea of the diffent options. Most SaaS charges between $8 - $15/month for 10 repositories. This can be expensive if you are mostly working on projects with clients that are not updated regularly.
|Source code kept local||Yes||-||Yes||-||-|