Security Assessment in Gmail API

Question

I am trying to configure Gmail API in a way so I can pull the inbox messages as well as respond against them. Basically, I am implementing a CRM and this one of the modules of that CRM. I got an email from Gmail verification support telling me that this needs to undergo a security assessment if your application can send Google suer data from a restricted scope to remote servers. For third-party security assessment, they mentioned that it may cost from $8,000 to $75,000. Is there some other way to tackle this? This is too much!