Setting up MSP + G Suite

I have a meeting with another local city in my area about getting them on as a managed client and G Suites for them. They have been a break-fix client of mine for the last year, but they have decided that they would like to transition to be a managed client. My question is, how does reselling G-Suite work?
So essentially, besides my company managing all their computers, networking equipment and server (which I recently install UniFi equipment and a FreeNAS server), they would want me to also manage their email accounts for them, adding/deleting users, etc. I’m trying to figure out the best way of going down this route to make it as seamless as possible for them.

Does the client currently use Active Directory, if so have a look at Google Apps Directory Sync this tool can automatically create and suspend users and groups when created and disabled in AD, there is also Google Apps Password Sync that can allow AD password changes to change the G Suite account password to match. This is hopefully just some information to help you manage if you choose to do so.

They do not, it’s just a 3 user small government town hall. I honestly think I currently put in about 2 hours a month there. They want managed services, so they don’t have to worry about anything, especially if the town grows or they become busier.

I have a town office as a client. The paper work from the State takes more time than the actual IT work most months. Just something to be aware of.

I’m not required to do paper work for either my local town governments that I support, which is nice.
I just send them an invoice through InvoiceNinja every month with what I did the previous month and it gets paid the same day.