Chrome: Collaborate your work with your colleague and customer on Google Apps is the best solution

Common Application: Documentation, Spreadsheet, Presentation and so on.

1. Google Apps(Google Docs, Spreadsheet, Calendar, Mail, Slide and so on) 
   • About the Product: https://www.google.com/enterprise/apps/business/products.html#more
   • Price: https://www.google.com/enterprise/apps/business/pricing.html
   • Free Trial for 30 days: https://www.google.com/a/signup/?hl=en&source=gafb-benefits-footer-en&ga_region=noram&ga_country=en#0
   • Top page: https://www.google.com/enterprise/apps/business
   • Google product forums: https://productforums.google.com/forum/#!forum/apps

Other common Application: Flow chart, Business Process, Floor plan, Org chart, Mock, UML and so on.

1. lucidchart https://www.lucidchart.com/

Development Code repository and so on

1. GitHub with google Drive(Might be worked but not final answer)https://productforums.google.com/forum/#!topic/drive/qLdqw7--YlY

Business Application and others:

You can find more suitable application such Financial application at https://www.google.com/enterprise/marketplace/home%20/

Local Vendor:

You might want to contact local vender to get help at http://www.google.com/enterprise/apps/business/partners.html

Printing: (Cloud ready printer)

You can print your Google Docs out to your office printer via internet using the function "Google Cloud printer" after you make gmail account for the printer which is named cloud ready printer. please check at http://www.google.com/cloudprint/learn/howitworks.html. And, Even it's legacy printer it's possible to implement. please refer at
https://support.google.com/chrome/answer/1069693?hl=en

Security:

Account authentication: You can keep Google account more secure with Google Authenticator which provide you to have one time password(passcode) with your current password. So, You can keep your account authentication securely. The solution is called Multi Factor Authentication(MFA, 2FA).

Google Authenticator at http://www.google.com/landing/2step/?utm_campaign=en&utm_source=en-ha-na-us-sk&utm_medium=ha

GitHub with Google Authenticator at https://help.github.com/articles/about-two-factor-authentication

Transmission: SSL/TLS

More about security stuff of Google Apps at https://support.google.com/a/answer/1360111?hl=en&ref_topic=29818

But if you want to implement data encryption of Google Drive, You must find application at https://www.google.com/enterprise/marketplace/home%20/.

Other(Network):

Your dedicated network goes to internet will be one of most important part to collaborate your work with your coworker and customer. So, You must keep maintaining the stability of network by backing the configuration up of router/firewall before you configured and updating the firmware. If you use wireless LAN in your office, you should use WPA2-PSK-AES with unique SSID, unique key, passcode these are not related to your personal information and company information. Also, You should not use default setting of Wi-Fi device. and, You should document about the necessary settings and contact point of support center to get work smoothly when there is an incident such failure of network. These should be kept securely. If you are not going to manage them by yourself, You should get support from local vendor. This is just security essential matter.

Recovery plan:

1. Setup your Smartphone(3G/4G) for your dedicated Network and do excise synchronizing the data between Google Drive in case mis-synchronization operation happen.

Out of scope:

1. Setup synchronizing the data between Google Drive at Google and shared drive on such OS X server is NOT necessary because these data will be kept on your local drive therefore it will be synchronized after the issue is fixed. But if you want to synchronize the data between Google Drive at Google and OS X server, you just make one more account for the server like you create your google account. but, There is no function to access from your desktop to the local server and It also will cost from operational view point.