G Suite Basic or Business

The three main editions of G Suite are

• Basic – $6 a user per month (start ups and 1-2 wo/man entrepreneurs use this but nearly always upgrade to Business)
• Business – $12 a user per month (most of our small to medium size businesses use this!)
• Enterprise – $25 a user per month (large scale businesses

Each lets you use G Suite as your organization’s core email, calendaring, and office collaboration solution. Unlike the Team Edition, you’ll need to verify your domain and modify several domain name records.

Three major differences between Basic and Business are storage, search, and compliance capabilities.

• Basic limits storage to 30GB per user, while Business level delivers unlimited storage (assuming you have at least 5 user accounts).
• Business includes Cloud Search, for Google-style intelligent search of your G Suite data — and works on the web and with a mobile app. Business also adds Google Vault, with data hold and archiving capabilities for policy and legal compliance management.
  We strongly Recommend GSuite Business for as most iPhones and Apple devices work best with IMAP email and fast syncing email across all devices you share is a REQUIREMENT. 

Google also offers editions for nonprofit, government, and education organizations. And for qualifying organizations, the nonprofit and education editions are free.