In Google compute engine, if predefined machine types don't meet your needs, you can create an instance with custom virtualized hardware settings. Specifically, you can create an instance with a custom number of vCPUs and custom memory, effectively using a custom machine type. Custom machine types are ideal for the following scenarios:
1. Workloads that aren't a good fit for the predefined machine types that are available to you.
2. Workloads that require more processing power or more memory but don't need all of the upgrades that are provided by the next machine type level.
In our scenario, we only need a memory upgrade. Moving to a bigger instance would also bump up the CPU which we don't need so we have to use a custom machine type. It is not possible to change memory while the instance is running so you need to first stop the instance, change the memory and then start it again. See below a screenshot that shows how CPU/Memory can be customized for an instance that has been stopped.
Ref: https://cloud.google.com/compute/docs/instances/creating-instance-with-custom-machine-type

https://cloud.google.com/logging/docs/audit

* The Datastore emulator provides local emulation of the production Datastore environment. You can use the emulator to develop and test your application locallyRef: https://cloud.google.com/datastore/docs
/tools/datastore-emulator

Coldline Storage is the perfect service to store audit logs from all the projects and is very cost- efficient as well. Coldline Storage is a very low-cost, highly durable storage service for storing infrequently accessed data.

Forwarding zones Cloud DNS forwarding zones let you configure target name servers for specific private zones. Using a forwarding zone is one way to implement outbound DNS forwarding from your VPC network.
A Cloud DNS forwarding zone is a special type of Cloud DNS private zone. Instead of creating records within the zone, you specify a set of forwarding targets. Each forwarding target is an IP address of a DNS server, located in your VPC network, or in an on-premises network connected to your VPC network by Cloud VPN or Cloud Interconnect.
https://cloud.google.com/nat/docs/overview
DNS configuration Your on-premises network must have DNS zones and records configured so that Google domain names resolve to the set of IP addresses for either private.googleapis.com or restricted.googleapis.
com. You can create Cloud DNS managed private zones and use a Cloud DNS inbound server policy, or you can configure on-premises name servers. For example, you can use BIND or Microsoft Active Directory DNS. https://cloud.google.com/vpc/docs/configure-private-google-access-hybrid#config-domain