Can Creator be used with Estimates? How to make estimates more functional...

I'd like to be able to customize the estimate section so if I sent a proposal to a client I can set up like a trigger system so that the customer can select optional services in the estimate. Is this possible and how can I do that?

I was thinking perhaps Creator can link up with Invoice somehow and then i can create options for the customer to add or delete in the estimate section. Or would I use Zoho form?

Hope that makes sense. I am new to Zoho so not sure how everything works yet.

Thank you.